Technology Explained

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC

Ben Stegner 29-06-2017

When you save a file on your computer, do you notice the few letters in the drop-down box below the name field? These are file extensions, and define which format your file saves as. Rarely is there a single format for one type of file, so you might be confused on how they differ and which are best to use.


Let’s compare two of the most popular file types each for images, documents, and audio files. Understanding the main differences between these major file types will help you decide which one to use in the future.

Know Your File Formats

Most digital information today takes three major forms — text, sight, or sound.  Whether you’re talking about web pages, movies, or any other form of entertainment, information is presented to the audience in one or more of those three.

So, if you’re a producer of information, how do you know what file format to use? The answer boils down to how you want to distribute or use that file.

Images: PNG vs. JPG

Many people use JPG and PNG files almost interchangeably, and don’t understand how they affect file sizes. However, more experienced users know that not only will smaller image sizes reduce overall server memory consumption, they’ll also increase page load speed.

File size is the major difference between JPG and PNG, but the reasons aren’t obvious until you take a closer look at the images themselves. Below is a picture of a forest scene in JPG format.


Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC JPEG Forest Image

This is a large image — over 1,000 pixels wide — and features vibrant colors and details. JPG (which stands for Joint Photographic Experts Group) has always been a popular image type for photographers sharing their work online The 14 Most Profitable Places to Sell Your Photos Online Here are the best places to sell photos online when you've taken photos you think people would be willing to pay for. Read More . This is due to the fact that the compression of highly-detailed images involves finding redundancies in those files and compressing the data. Thus, beautiful images like the one above can still be presented with little quality loss. The resulting file size is a fraction of the original that may come straight from a digital camera.

However, because of the compression method, JPGs have some issues with contrasting edges in photos. This is most prevalent with text, signs, and the like. But if you zoom in far enough even into a high-quality image like the one above, you can see the quality reduction along those straight edges in the form of  a “shadow” along the edge.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC filetypes2


After saving the file multiple times, you can see the quality of the image reduce even further when you zoom back in. In this case, the meshing between edges becomes more pronounced, and you can see near highly-contrasting colors that there’s a greater amount of distortion.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC Forest Multiple Saves

The PNG Difference

Let’s next take a look at a highly-detailed PNG image of a park with strong contrasting black and white colors. Such an image would do a number to the JPG compression process. It isn’t too apparent from a distance, but much more obvious as you zoom in.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC filetypes3


However, zooming into the PNG image, you can see that there’s no “shadow” effect or any significant distortion on the contrasting edges.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC Bench PNG Comparison

PNG stands for Portable Network Graphics, and was originally created as a replacement for the outdated GIF format. The PNG compression algorithm is non-lossy How Does File Compression Work? How does file compression work? Learn the basics of file compression and the difference between lossy versus lossless compression. Read More . When you save a PNG file again, the quality of the saved image is identical to the original.

Another huge benefit to PNG files is that they support image transparency. This allows you to use a transparent icon or image that blends seamlessly into a background without any ugly outline. See below the JPG image on the left, and the PNG image on the right over a blue background.


Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC JPEG vs PNG Transparency

So, how do you choose which image format to use JPEG, GIF, or PNG? Image Filetypes Explained and Tested Do you know the differences between JPEGs, GIFs, PNGs, and other image filetypes? Do you know when you should use one instead of the other? Fear not, MakeUseOf explains everything! Read More ? Basically, if you want to provide high-quality photographs, save once as a JPG file. Avoid making too many modifications and performing multiple saves as you’ll lose quality.

On the other hand, if you’re creating icons or images with sharp contrasting colors — like images with text for example — then go with a PNG. Also, PNG is particularly valuable in web design when you need transparent images. Just keep in mind that PNG file sizes are typically larger than JPGs, so plan accordingly.

Of course, JPG vs RAW is another image file format comparison you need to consider—which format is best for snapping photographs RAW vs. JPEG: Which Is Best for Your Photographs? Should you shoot your photographs in RAW or JPEG? Here are the pros and cons of both formats, essential for photographers. Read More ?

Documents: DOCX vs. PDF

Most people have sent a document online — whether it’s offering a formatted document via a website, or email documents when applying for a job. The most common document formats are Microsoft Word documents (DOCX) and Adobe PDF files.

Here’s what happens if you try to open a DOCX file from a web page:

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC Download DOCX Webpage

That’s right, Word documents don’t work as embedded files — you can’t view them inside a browser because it’s a proprietary file format. You could open it via Office Online Don't Pay for Microsoft Word! 4 Reasons to Use Office Online Instead Microsoft Office Online offers free web versions of Word, Excel, and PowerPoint. Here's why you should give it a try today. Read More , but a novice user might not know to do that. If you aren’t certain whether your recipient has Microsoft Word installed, then it’s better to present your document as a PDF. This is easy thanks to a variety of PDF creation methods available.

You might think that Adobe Acrobat Reader is the de facto PDF reader, but you don’t really need it anymore thanks to PDF viewers built into browsers PDF Reader vs. Browser: Which PDF Viewer Is Best for You? A PDF reader is often one of the first tools people install on their new computer. It's not glamorous or sexy, but it's a vital tool in your productivity arsenal. Or is it? Read More . So with a browser like Google Chrome or Microsoft Edge, your recipient doesn’t even need to have a desktop reader installed.

Are PDFs Always the Best Choice?

So, it might seem that PDF is always the way to go when you want to distribute documents. You can embed them in web pages, work well for small eBook formats, and they transcend operating systems. Do they have any downsides?

Of course, the catch is that editing a PDF is clunky 5 Free Tools to Edit PDF Files PDFs are universally useful. However, they fall short when it comes to editing. We're here to show you the best free tools to edit your PDF files. Read More , and advanced editing requires expensive software. When you’re collaborating with someone on a project, it’s important to have the tools that Microsoft Word offers for editing and collaborating. So, there’s a place for the DOCX format in sharing documents, but it comes down to how you want to use that document and why you’re sharing it.

If you’re sure that all recipients have Word installed and want them to edit it further, use DOCX. For times when you want to preserve a document’s format and want compatibility across all platforms, go with PDF. You should know how to reduce the size of a PDF file How to Compress a PDF, Reduce the File Size, and Make It Smaller This guide covers how to make a PDF smaller and manually reduce its size using simple programs and tools. Read More for more efficient sharing, too.

Audio: MP3 vs. FLAC

Perhaps you’re thinking of recording yourself playing guitar, or maybe you are buying music and have the choice to download a lossless FLAC or a compressed MP3. Which do you choose, and why?

This topic has seen plenty of debate around the internet. Plenty of music fans feel that MP3 files are a high-enough quality that they’re indistinguishable from the original recordings. Other folks — usually those within the music recording community — feel that the quality difference is quite noticeable. We’ve even tested audio compression’s effects How Audio Compression Works, and Can You Really Tell the Difference? In this article, we'll take a look at how music compression works, and whether it has any real effect on how your music actually sounds. Read More if you’re interested.

To take a closer look at this, we downloaded a free classical song in lossless FLAC format. Played in Audacity, it was apparent that the music was crisp and clear.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC filetypes11

The first test was exporting the original recording as an MP3 file using the default Audacity export settings. Then, opening both files side-by-side, we took a closer look at the sound files.

You can see subtle differences when you look at them together. It isn’t quite as obvious in this snapshot, but if you look close, you can see that the graphs for the MP3 file (the bottom two tracks) are not quite as dark as the top FLAC graphs. This is most apparent in the first section of the graph, where the far edges of the response (shown by the first arrow) are definitely more defined in the FLAC file.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC filetypes12

I didn’t notice a substantial difference when listening to the two audio files, but music recording experts might pick up on distinctions between them.

Changing the MP3 Bitrate

Checking the MP3 export settings in Audacity 7 Audacity Tips for Better Audio Editing on a Budget Here are several useful Audacity tips that will make your life much easier when editing audio, especially if you're on a budget. Read More , I saw that it was exporting an MP3 at a bitrate of 128 kbps. This is great for reducing the file size 5 Tips for Optimizing Audio File Sizes If you've ever wanted to reduce the size of an audio file but weren't sure how to do that without impacting the quality of the recording, here's everything you need to know. Read More , but doesn’t provide the best quality.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC filetypes13

So, I tweaked this up to the maximum value — 320 kbps — and then repeated the exercise above.

This time, the differences between the FLAC track and the MP3 track were almost indistinguishable from each other. Given, the 320 kbps MP3 was much larger than the 128 kbps file — 12 MB versus 5 MB, but it was still half the size of the original 24 MB FLAC file. Again, in the image below find the MP3 track as the bottom two graphs and the FLAC track at the top.

Know When to Use Which File Format: PNG vs. JPG, DOC vs. PDF, MP3 vs. FLAC filetypes15

So, how do you decide on an audio format? If you’re recording music and want to maintain the highest possible quality, FLAC or any other lossless format is obviously the way to go. This will ensure that you’re capturing every nuance of the performance. Thankfully, external hard drives let you save tons of files for a low cost, so saving such audio files isn’t a huge deal.

However, if you’re a collector of music and you just want to store as much as possible on your portable player, MP3 is clearly the way to go. If you run a podcast and want to ensure that your listeners are not waiting forever for an episode to download, MP3 is the best choice.

Don’t forget that there are plenty of other audio formats out there The 10 Most Common Audio Formats: Which One Should You Use? You know about MP3, but what about AAC, FLAC, OGG, or WMA? Why do so many audio file formats exist and is there a best audio format? Read More , and a huge world of difference between MP3 and MP4 What Is MP4? The Difference Between MP3 and MP4 MP3 and MP4 make up two of the most common media file formats today -- but despite the apparent similarity, the two couldn't be more different from each other. Here's our comparison breakdown. Read More !

Which Formats Are Your Favorite?

We’ve compared the differences between major formats of images, documents, and sound. In all cases, the format you opt for almost always depends on where you draw the line between quality and size How to Reduce Video File Size Without Losing Quality Is your video file taking up way too much space? It's time to encode, compress, and tweak it so that it shrinks in size without losing any noticeable quality. Read More . There’s a place for both, but you need to carefully consider how you’re going to use that file, and choose the right file format for the purpose.

When preserving quality is of the utmost importance, a lossless format like FLAC or PNG works best. Universal, space-friendly formats like PDF and MP3 ensure the lightest strain for those viewing them, and the best compatibility.

Does this help with your own file format dilemmas? Do you have any other file formats you prefer above those mentioned above? Share your own thoughts and insights in the comments section below.

Image Credit: Ulza via

Related topics: Digital Document, MP3, PDF.

Affiliate Disclosure: By buying the products we recommend, you help keep the site alive. Read more.

Whatsapp Pinterest

Leave a Reply

Your email address will not be published. Required fields are marked *

  1. Galvanized Photography
    January 13, 2018 at 10:37 pm

    Great read! This article is very clear and concise. And let's not forget helpful! Thank you!

  2. Justin Moore
    December 31, 2017 at 6:04 pm

    Great article! Broke it down so it was easy to understand and very nice visual aids. I was just looking for more info on PDFs but read through and got answers to questions I didn't even know I had. Thanks.

    • Ben Stegner
      January 2, 2018 at 3:13 pm

      You're welcome; I'm glad it helped you!

  3. Doc
    July 3, 2017 at 9:54 pm

    PNG files CAN be lossy:

    Also, if you're loading up a JPEG and re-saving it, you're obviously not a professional. The CORRECT way to edit a JPEG is to save the "work" file into something like a BMP, PSD or XCF (GIMP version of Photoshop's PSD), in an uncompressed format, and only "export" to JPEG once. This preserves the uncompressed image, along with any layers and history, and there will be no repeated loss of detail.

    There's no real reason to use FLAC, especially with its huge file sizes. Anyone who says they can tell the difference between a well-produced MP3 and analog audio (vinyl or tape) is delusional.

  4. Stephan Huebner
    July 3, 2017 at 9:07 am

    It should be noted that there are quite a few better alternatives for MP3. Some of which with comparable file sizes and still better audio quality than MP3, some resulting in much bigger files but no information lost. Examples would be ogg, aac, flac, aiff or wav. Another, relatively new format would be opus (I think created by the people behind ogg).

    TL;DR: Don't use MP3 for your own collection, even if you want a lossy format. There are far better options.

  5. Glut It Podcast
    February 19, 2017 at 7:28 am

    We understand that music addiction works as a surrogate for missing human bonds. Songs can pierce the heart directly; it requires no mediation. Weekly Tropical House mixtapes uploaded each and every Wednesday. Hear us on AudioMack!

  6. Nick Nolte
    July 23, 2016 at 3:16 pm

    Frankly compression formats except video are pointless in the age of broadband, but we keep using them because it's still quicker than downloading the raw image.

    A distributor like Apple still uses compressed music because they are serving millions of users and they want to keep their (apple) data bill low. As a customer I'd much rather be receiving a decrompressed version of the music (I'm one of the people that can tell the difference between a high quality MP3 and the same song playing on compact disc).

  7. Vince
    April 27, 2016 at 12:59 am

    Thank you... I've always wondered what the differences were in the common formats. This helped me understand.

  8. Spartan
    March 2, 2016 at 12:05 am

    Very badly edited article, I even spotted "their" in place of "there".

    • ikinone
      March 18, 2016 at 6:39 pm

      One mistake doesn't make it a 'very badly edited article'...

      • Greg
        May 25, 2016 at 7:30 pm

        "These days, website owners use JPG and PNG files almost interchangeably, and many bloggers on services like or Blogger and are completely oblivious to the effects of large image sizes will actually use those images interchangeably"
        Letting this sentence get published made it a very poorly edited article

        • dfafdf
          August 2, 2016 at 6:28 am

          you were reading the article for the wrong reasons

  9. Connie Tolman
    January 14, 2016 at 4:14 pm

    Very easy to understand. I have tried for years to figure this out and here it is all on one page. Bravo!

  10. Sarah Jane
    July 21, 2013 at 7:23 am

    As a graphic designer i always send my clients sample graphics in PNG format. Although in PhotoShop you can save a JPG with the highest quality, you will always notice that there's still some compression. So as far as images are concerned, i'm more for PNG than JPG. Sometimes if i have several images to send to a client, i simply put everything in a single uncompressed PDF file.

    This is done using a free image to pdf converter :

    For documents, i use PDF. When sending clients contracts, agreements etc... i always send these in PDF format. I have installed a kind of "driver" that i downloaded from . After my agreement/contract etc... is ready in MS Word, i simply click on File > Print, choose the PDF Driver and a PDF file will be created.

    For music, it's always MP3 :)


  11. Chetan Chandgothia
    April 4, 2013 at 5:45 am

    Was pretty boring!

  12. Olle Andersson
    March 14, 2013 at 5:37 pm

    To show differences you should use the same picture. Also it would be nice if you compared the .jpg vs .png file sizes for the same picture. Today the .png is sometimes just like the old (I hope forgotten) .bmp-format.

    • Doc
      July 3, 2017 at 9:56 pm

      BMP (Windows BitMaP) is a VERY old format, and doesn't allow transparency or advanced compression (IIRC, it only allows RLE compression, which is ancient). PNG is vastly superior to BMP or GIF.

  13. Paul Girardin
    February 12, 2013 at 5:30 am

    Thanks for sharing!

    More things learned today!

    I kept a copy (made with Clearly) for future reference!

  14. Robert Backlund
    February 12, 2013 at 4:12 am

    If I send a friend a document I send them both rtf and also odf, I know that the Open document format is not widely used yet but it should be. In one of your responses to a comment you comment on the difficulty that people who use Microsuck's Office with being able to open files created in an earlier version of MS Office. This is typical of a company like MS, where they hook the average user and then continually rape them with version updates that use a different file type as their default and make the new program not able to be backward compatible. If I send someone a disk I send them the document in ODF and also include the latest download for Libre Office. I have had many very positive comments from people who have never heard of either Open Office or Libre Office. The scary thing for me is all the very important documents that have been created by various governments using MS Office over the years that think these files will be able to be opened and read by some distant future MS Office package and that assumes that MS will still be around in 50 to a hundred years. ODF should become the world standard, MS hates it because they cannot control this standard and because of it they would loose their cash cow.

    • Doc
      July 3, 2017 at 9:58 pm

      Was considering replying to this with a reasonable reply...then I saw the anti-Microsoft rant and gave up all hope.
      Also, loose lose.

      • Robert Backlund`
        July 4, 2017 at 12:44 am

        Sorry you feel that statements of fact constitutes an anti MS rant. I am sorry that you cannot handle the truth about MS and MS Office. Since posting this reply way back in 2013 the ODF file format has become the standard and more and more European Countries and cities are using Libre Office that is available on every OS that runs on a laptop or desktop computer. No where in my post did I say that you should stop using MS Office, I only gave valid reasons to use programs that out put ODF file formats something that MS Office does not do. If you have never used or even looked at Libre Office I would encourage you to try it out because it will not cost you a dime, only the time to download it. Other free and very capable Open Source programs to try are The GIMP (similar to Photoshop with lots of tutorials on Youtube), Inkscape (similar to Corel Draw and Adobe Illistrator also with lots of Youtube tutortials, Scribus a very powerful and useful desktop publishing software, Krita very similar to Corel Painter that uses all of the Wacom and other drawing tablets, is great for fine art and the last one if you are interested in 3D modeling, rendering as well as animation is Blender.

  15. Nevzat Akkaya
    February 11, 2013 at 11:20 am

    Thanks for this very informative article. I've bookmarked it already. (You know, people forgets :)

  16. Lisa Santika Onggrid
    February 11, 2013 at 7:46 am

    I prefer downloading MP3s. I can't hear the difference between lossy and lossless and it's a pain to download a full album in FLAC.

  17. Anonymous
    February 8, 2013 at 6:03 pm

    I learned a lot from this article and can now work better on my website and the right file formats. Thanks Makeuseof!

  18. Axel
    February 8, 2013 at 5:40 pm

    Under the first illustration, it should be "their" not "there".

  19. Josh Barrett
    February 7, 2013 at 10:59 pm

    The holy grail of document files (universally readable and writable) is .txt but it doesn't work with images or formatting, so if you need that use the similar .rtf format, which is almost as universal.

    • ozmark
      February 8, 2013 at 5:41 am

      Right on, Josh. You'd think the downside of .doc would be painfully obvious by now, even by ms word users battling version challenges. I'm really surprised it's being put forward as an option here.

      • Doc
        July 3, 2017 at 10:02 pm

        Bah. LibreOffice can read and write DOCX and XLSX, with some loss of features (most of which are edge use cases, with idiots using seldom-used features). OpenOffice lost market share because it wouldn't play nice with OfficeXML; LibreOffice leapfrogged them and took over. :)

    • Doc
      July 3, 2017 at 10:01 pm

      TXT is hardly "universal," with the Windows (CR/LF) and Unix (LF) line ends, UTF-8 vs. ANSI vs. UCS-2; and neither is RTF, although many OSes can read it. If you want a "universal" document format, Adobe opened up the PDF standard some years ago, it includes images (although they can be degraded by being downsized during document preparation if you're not careful).

  20. ozmark
    February 7, 2013 at 10:51 pm

    For read-only docs, ALWAYS send PDF's. For collaboration, use Google Docs or similar. If you must send a writeable file, use ODF.

    • Lisa Santika Onggrid
      February 11, 2013 at 7:48 am

      ODF isn't actually widely supported, tho.

      • Mr_Green_PL
        February 11, 2013 at 1:19 pm

        But one can install plugin (for MS apps) or download opensource software (openoffice, libreoffice...)

        • Doc
          July 3, 2017 at 10:03 pm

          Corporate users will likely forbid either - an unknown, unproven converter, and won't allow OpenOffice or LibreOffice on their computers. Best to ASK before sending!

  21. Mar Viv
    February 7, 2013 at 9:28 pm

    I never really thought about all this until now, I always wanted to know the difference between flac and mp3 but never really felt the need to find the difference. Thank you for this insight. Love your articles Ryan.

    • Lisa Santika Onggrid
      February 11, 2013 at 7:48 am

      Can you hear the difference? I honestly can't.

      • LuisGSF
        February 12, 2013 at 4:28 pm

        You might not hear the difference in most new recent material if you are not trained and with proper (good) audio equipment, as currently, because radio loudness war and Mp3 popularity, most recordings are already overly compressed, but if you look into older material you will probably hear the difference. Try Phil Collins "In the air tonight" in FLAC and Mp3 and you will.

        • null
          June 25, 2013 at 9:39 pm

          Human ears usualy cant hear those noises that are removed with mp3 V0 which better in many ways than any constant mp3 bitrate.

  22. ReadandShare
    February 7, 2013 at 8:02 pm

    +1 to Fred Conover's comment above.

    Not just quibbling with grammar, but the comparison between JPG and PNG is downright confusing to me. So JPG is good except when there are sharp edges? And if PNG is good for sharp edges then why isn't it also good for big, beautiful, crisp images? I assume that it's because PNG takes up more space? But that wasn't spelled out.

    • Lisa Santika Onggrid
      February 11, 2013 at 7:48 am

      If you do multiple edits it's better to use PNG as you'll not lose anything, but JPG will suffice when you release the final product (no more edit)

      • gzuckier
        February 16, 2013 at 7:27 am

        What about that artifact where blocks that should be a gradient of shading are all set to the same color, so that you get this blotchy blocky effect? Is that jpg only, or png also?

        • Lisa Santika Onggrid
          February 16, 2013 at 12:59 pm

          As far as I know it's JPG thing, because PNG can render it just fine, unless the original picture is already low-quality.

      • Doc
        July 3, 2017 at 10:04 pm

        Of you do multiple edits, KEEP THE ORIGINAL MATERIAL, then edit from there. Export to JPEG only as the last step.

  23. Fred Conover
    February 7, 2013 at 7:19 pm

    "...These days, website owners use JPG and PNG files almost interchangeably, and many bloggers on services like or Blogger and are completely oblivious to the effects of large image sizes will actually use those images interchangeably..." <== Desperately needs to be reworded, please.

    (Great article, though...thanks a ton!