tooloora

Compress Image — shrink JPG, PNG & WebP in your browser

Pick a quality or a target size in KB, compress several photos at once — processed locally, nothing is uploaded.

Runs locally — nothing is uploaded

Drop images here or click

JPG, PNG or WebP · multiple files supported · stays local

Runs locally in your browser – no upload.

Compress an image — in your browser

Pick your photos, set a quality or a target size in KB and download the result — single files or a ZIP for batches. Compression runs entirely in your browser using WebAssembly codecs (MozJPEG, WebP, OxiPNG): your images are never uploaded, and you see the before/after size down to the byte.

Quality or target size — which should I use?

The quality slider is right when you want to control how the image looks: 80 is a good default for photos. The target size in KB is right when a form or portal enforces a hard limit: the tool binary-searches for the highest quality that still fits under your limit — with at most 8 encoding passes. If the target is physically impossible for that image, you get an honest message with the smallest size reached instead of a silent overshoot.

Why WebP is often the better choice

According to Google's WebP compression study, WebP files are 25–34% smaller than JPEGs at equivalent visual quality. The catch with other tools: Safari can display WebP but cannot create it. This tool ships its own WebP encoder — WebP export works in Safari too.

Honest limits

  • PNG is lossless: the quality slider only affects JPG/WebP; PNGs are re-optimised losslessly with OxiPNG, so savings are smaller there.
  • Not every image shrinks: files that are already heavily compressed can even grow on re-encoding. The tool warns you instead of celebrating a worse result.
  • EXIF is dropped: re-encoding removes metadata (GPS position, camera details) — usually a privacy win, but keep the original for your photo archive.

Frequently asked questions

Are my photos uploaded to a server?

No. Compression runs entirely in your browser using WebAssembly codecs served from this site. Your images never leave your device — you can even use the tool offline.

How does the target size in KB work?

The tool searches for the highest JPEG/WebP quality that still fits under your target, re-encoding up to 8 times. It counts 1 KB as 1000 bytes, the stricter of the two readings, so the result also passes upload limits that were configured in plain bytes. If the target is impossible for that image, it says so honestly and offers the smallest size it reached.

Does the target size work for PNG too?

No, and the tool no longer pretends it does: PNG is compressed losslessly, so there is no quality dial to search. The target size field is therefore switched off while your selection would come out as PNG. Choose JPG or WebP as the output format if you need to hit a fixed KB limit.

Can the result end up bigger than the original?

The target search is capped at the source file size, so a target that is more generous than your file cannot push the compressor into enlarging it. If even the lowest quality stays above the original — which happens with already heavily compressed files — the tool names that file and tells you to keep the original.

Should I convert to WebP?

Usually yes for web use: according to Google's WebP compression study, WebP files are 25-34% smaller than JPEGs at equivalent visual quality. This tool encodes WebP with its own codec, so it also works in browsers like Safari that cannot write WebP natively.

Why did my image not get smaller?

Already heavily compressed images, small graphics or PNG screenshots may not shrink further — sometimes a re-encode is even bigger. The tool compares before/after and warns you when there is no benefit, so you can keep the original.

What happens to EXIF metadata?

Re-encoding drops EXIF metadata, including GPS coordinates and camera details. That is a privacy feature — but if you need the metadata, keep a copy of the original file.