Whether you’re designing a website, writing a blog post, or sharing your latest photography shots, sometimes you’ll find yourself with a handful of images that need to be processed en masse — and doing them one by one can end up being a huge waste of time.
There are plenty of batch image tools out there, but many of them require installation and most are limited to one particular operating system. In a lot of cases, it’s just faster and more convenient to use free online tools instead because they’re accessible from anywhere at any time.
So we’ve compiled a list of the best online tools for batch image processing and categorized them in three ways: resizing, optimizing, and converting. Bookmark the ones you find useful and start using them now!
Image Resizer Tools
Image resizers can be tricky, not only because of file size considerations, but also because resizing can affect the quality and clarity of images. In this sense, some resizers are objectively better than others, and that’s why the best ones are those that give you fine control over quality.
Bulk Resize Photos has the easiest interface. Just drag your images onto the site — as many as you want — and you can scale in five ways: percentage, longest side, width, height, or exact size. Everything is client-side so it’s really fast and there’s no uploading necessary.
Or use the advanced settings to change formats between JPG and PNG, adjust image quality, set a background color, and even add padding to prevent stretching.
BIRME, which stands for Batch Image Resizing Made Easy, is simple but flexible. Drag your images onto the page and set the new width and height. Depending on which resize option you select, it will scale or crop to fit your dimensions.
It can also add some border padding and alter quality settings (for JPGs). Resized imaged are downloaded as a single ZIP file.
Here’s another drag-and-drop site that’s on par with the two above, only a little more restrictive. Upload your images, select a width between 30px and 1500px, a quality between Low, Medium, High, and Best, and then choose whether you want to convert to JPG, PNG, or keep the original format.
The restrictions: You can bulk resize up to 10 images at once, size should not be more than 15 MB per image, and neither width nor height can exceed 6000px on any image. The site is available in Russian and English too, in case that matters to you.
The nice thing about PicGhost is that you can upload your own files or import them directly from Facebook, Flickr, or Picasa.
The restrictions: Upload up to 40 images at once and size should not be more than 10 MB per image.
Not only can you resize in a variety of ways, but you can also add watermarks and edit each image using an online editor called Aviary. I’d personally only use this tool for resizing though.
PicResize is a batch resizing tool that we’ve mentioned before. It’s still useful and it gets the job done, but it’s a little behind when compared to the aforementioned resizers. Use it if the above tools aren’t available to you or you don’t like them for some reasons.
If you switch to the non-batch version of PicResize, you can also crop and add special effects to your images.
Image Optimizer Tools
Image optimizers have one primary focus: to reduce the file size of an image as much as possible while impacting the quality of that image as little as possible — all without resizing or cropping the image.
TinyPNG is arguably the best image optimization tool on the web. Despite the name, it can compress both PNGs and JPGs, and there’s absolutely nothing you have to do other than upload the images (which uses a lovely drag-and-drop interface).
Once uploaded, TinyPNG automatically compresses using a lossy method that maintains the perfect balance between quality and file size reduction. Files can be downloaded individually, as a single ZIP file, or moved to your Dropbox account.
Optimizilla is very similar to TinyPNG in that you just drag-and-drop PNGs and JPGs and it does most of the work for you. However, with this one, you can control the final quality of the images (between 1% and 100%) on a per-image basis.
The downside is that you can only process 20 images at a time. Files can be downloaded individually or as a single ZIP file.
Kraken is another drag-and-drop tool that’s a bit more restrictive than the above tools, but has one big advantage: you can choose whether to compress using a lossy or lossless method. Download resulting images individually or as a single ZIP file.
The restrictions: Up to 1 MB per image and a total of 50 MB per month. Or you can get a premium subscription to increase the file size limit to 32 MB, the monthly upload limit to gigabytes, and unlock extra features like resizing and Dropbox synchronization.
We’ve lauded the benefits of Kraken before, but unless you need the lossless compression, TinyPNG or Optimizilla may fare better for you.
Image Converter Tools
Different image formats have different pros and cons — check out our comparison of JPG, PNG, and GIF — and often it makes more sense to prioritize one format over others. These tools come in handy when you want to switch a lot of images to a particular format.
Raw.Pics.io isn’t just a handy tool, but it’s beautifully designed too. It makes you want to use it, and that’s rare among online tools (which tend to be hastily thrown together).
As a photography-centric tool, Raw.Pics.io mainly supports RAW source files in the following formats: DNG, CR2, NEF, ARW, ORF, PEF, RAF, PDF, or JPG. Images can be exported as JPG, PNG, or WEBP. Only JPG source images can be resized.
CloudConvert is an incredible tool for any kind of file conversion. You have to connect your cloud account (either Dropbox, Google Drive, OneDrive, or Box) and pick files that way. No uploads allowed. But it supports dozens of image inputs and outputs so it’s well worth it.
For free, you get 25 conversion minutes per day, which actually isn’t that bad. You also get 5 concurrent conversions, 1 GB max file size, and bumped down to low priority if there are lots of others using CloudConvert at the same time. For more freedom, you can upgrade to a premium subscription starting at $8 per month.
Did We Miss Any Tools?
Even though image size and quality are important for websites and blogs, remember that image SEO is just as important for maximizing the amount of search engine traffic you capture. Don’t neglect that aspect.
Note that if you’re using one of these tools as a photographer and you have aspirations to be professional or semi-professional, we recommend learning to use something like Photoshop or Lightroom instead.
And don’t forget these photography practice exercises!
If we missed any other batch resizers, optimizers, or converters, please let us know in the comments below! Otherwise, tell us which ones are your favorite and what you used these tools for. We’d love to hear from you!