Image Compressor

Make an image smaller in bytes while deciding for yourself how much quality to give up. The compression runs on a canvas in your browser, so the photo is never uploaded and you can see the result before you keep it.

Live demo · real result from this tool

Drop images here

or paste with Ctrl+V · nothing is uploaded

Compress by
Resizing first is the biggest saving for photos shown on screens.

Your result appears here — processed on your device.

Processed on your device — nothing is uploaded.

How to use Image Compressor

  1. Choose an image, or drop it onto the page.
  2. Pick the output format. Keep PNG only if you need transparency or the image is flat colour.
  3. Move the quality slider and watch the estimated size and preview update.
  4. Download when the trade-off looks right.
  5. Transparency survives in PNG and WebP, and is flattened to white in JPEG.
  6. EXIF metadata, including GPS location, is dropped on re-encode.

Lossy and lossless are different jobs

JPEG and WebP are lossy: they discard detail the eye is poor at noticing, and the quality slider decides how much. PNG is lossless, so the only savings come from better encoding of the same pixels, which is why a PNG photo barely shrinks while a PNG screenshot of flat colour shrinks a lot. If a photo is stuck as a large PNG, converting it to JPEG or WebP will do far more than any PNG optimiser.

Where the quality slider stops helping

Between 100 and about 80 the file shrinks fast and the difference is hard to see. Below roughly 60, JPEG starts showing blocky artefacts around sharp edges and text, and halos along high-contrast lines. For photographs destined for the web, 75-85 is the usual sweet spot; for an image with text in it, stay high or use PNG.

Resize before you compress

The largest single saving is usually dimensions, not quality. A 4000px photo displayed in a 800px column carries twenty-five times the pixels it needs. Resize to the size it will actually be shown at, then compress; doing it the other way round throws away quality you then discard anyway.

Frequently asked questions

Why is my compressed JPEG still large?
Usually because of its dimensions rather than its quality setting. A phone photo has far more pixels than a web page shows, so set Longest side to the size it will be displayed at; that saves more than the quality slider. If the result is still not smaller than the original, the tool says so and you can keep the original.
Can I compress an image to a specific size in KB?
Yes. Switch Compress by to Target size and enter the KB. The tool uses the highest quality that fits and, if even a low quality is too big, scales the image down as well. The result says which quality and scale it used, or why the target could not be met.
Is my data secure?
Absolutely. This tool runs 100% locally in your browser. Your files are never uploaded to any server.
Why did my PNG get bigger?
Re-encoding a PNG that was already optimised can add bytes, because the encoder here is tuned for speed in a browser rather than for the exhaustive search a dedicated optimiser does. If the output is larger, keep the original — the tool shows both sizes so you can tell.
Does compressing remove the location data from my photo?
Yes. Re-encoding writes a fresh file with no EXIF block, so camera model, timestamp and GPS coordinates are all gone from the output. That is usually what you want before posting a photo publicly.

Written by the ToolsRift team · Last updated

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