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Bulk Image Compressor: Many Photos to a KB Size

Compress many JPG, PNG, WebP or HEIC images at once to 20 KB, 50 KB, 100 KB or any size, each one hitting the target. Download them one by one or as a ZIP.

Private · on device. Runs in your browser: your file is not uploaded. No sign-up.

JPG, PNG, WebP or HEIC, as many as you like
Every image hits the target. Each one is compressed on your device with the same exact-size search as the single-image compressor: the highest quality that still fits under your limit.

A whole folder of photos under one KB limit

Forms, listings and email attachments often take many images with the same limit: 10 product photos under 100 KB, a set of documents under 200 KB each, a photo album small enough to send. Doing them one by one is slow, and a quality slider applied to all of them gives some files far under the limit and others still over it.

Here every image gets its own exact-size search, so each lands just under the target, as large and sharp as the limit allows. The list shows each file's size before and after and a tick when it fits, and the totals show how much you saved.

Getting the best result at small sizes

  • Set a longest side for tight limits. A 4000 px photo compressed to 20 KB loses almost all detail; the same photo at 800 px looks clean at 20 KB.
  • Use JPG for photos. It is what upload forms expect and it compresses photos far better than PNG.
  • Keep PNG for screenshots and logos, where sharp edges and flat colours matter.

Need just one image, with a minimum size as well as a maximum? Use the single image compressor. To fix dull or dark photos first, run them through the photo enhancer.

Frequently asked questions

Does every image really end up under the size I choose?

Yes, or it says so. Each image is encoded several times at different settings and the largest file that still fits under the limit is kept, the same exact-size search the single-image compressor uses. If an image cannot get under the limit without becoming unusable (a 12-megapixel photo squeezed to 20 KB), its row says so and suggests setting a longest side first.

How is 50 KB counted: 50,000 or 51,200 bytes?

Portals differ, so the compressor aims under 50,000 bytes, which passes either way. The same goes for every preset and any custom size you type.

Are my images uploaded?

No. Each image is compressed by your own browser, one after another, and the ZIP is put together on your device too. Nothing is sent anywhere, so it works on a slow connection and with private documents.

What does the Quality option do?

Instead of a size target, every image is saved at the JPG or WebP quality you pick (90% looks the same as the original for photos, 60% is much smaller). Use it when you want consistent quality rather than a size limit.

Why did a PNG come out as a JPG?

PNG is lossless: the only way to make it much smaller is to shrink its pixels, sometimes to a thumbnail. Under "Keep each format", a PNG that would have to shrink a lot is saved as a JPG instead (or WebP when it has a see-through background), which keeps it full size at the same KB. Choose PNG under Format to force PNG.

Can I stop halfway?

Yes. Cancel stops after the image being compressed; everything finished so far stays downloadable, and pressing Compress again carries on with the rest.

Requirements this tool handles