Compress image to 20MB
Drop a photo in, and it comes back under 20MB at the best quality that still fits. Everything runs inside this browser tab — your files are never uploaded.
Who asks you to compress image to 20mb
Used by document management systems and some applicant tracking systems for combined attachments.
Whatever the reason for the limit, the practical problem is identical: a modern phone camera produces files of several megabytes and the form in front of you will not take them. What you need is not "smaller" but "under this specific number", which is exactly what a plain quality slider cannot give you.
Resolution you keep at 20MB
A useful rule of thumb: a typical photograph at moderate quality costs roughly an eighth of a byte per pixel. Working backwards from 20MB, the practical ceiling is around 174,762,667 pixels — approximately 16190 by 10790. Stay at or below that and the encoder has enough budget to look clean. Push well past it and you are spreading a fixed budget over more pixels, which is where blocking and smeared detail come from.
This is an order-of-magnitude guide, not a promise, because content matters enormously. A flat product shot, a screenshot or a scanned signature compresses several times better than the estimate. A noisy night scene or dense foliage compresses considerably worse, since noise is incompressible by design. When you compress image to 20mb here the tool measures the real encoded file rather than estimating, so the answer is honest for your specific image.
If the estimate says your photograph is well past that pixel budget, the better move is to reduce the dimensions deliberately before you compress image to 20mb, choosing what to lose rather than letting the encoder decide. A half-resolution image at a generous quality setting almost always looks better than a full-resolution one squeezed to the same number of bytes.
How this tool can compress image to 20mb exactly
Most compressors give you a quality slider and let you find out afterwards how big the file turned out. That is the wrong way round when you have a hard ceiling. This tool works backwards from the number: you ask it to compress an image, and it searches for the encoder setting that lands just underneath.
The search is a binary search over the JPEG or WebP quality parameter. It encodes at the midpoint of the remaining range, checks the byte count against 20MB, and moves the range accordingly. Nine passes narrow the setting far finer than the eye can resolve, and every pass keeps the best result that fit — so what comes back is the highest quality version that still fits, not the first one that happened to work. Nine passes is also fast enough that you can compress image to 20mb, look at the result, change the number and run it again without ever waiting on a progress bar.
When quality alone cannot get there, the tool reduces pixel dimensions in steps and searches again. That order matters: dropping quality first preserves your framing, while shrinking first throws away detail no quality setting can recover. Final dimensions are listed next to the file whenever a resize was needed, so an attempt to compress image to 20mb never quietly returns something smaller than you asked for without saying what it gave up to get there.
JPG, PNG or WebP at 20MB?
At 20MB you have room to prioritise fidelity over raw size. WebP is the best default: it holds detail noticeably better than JPG at the same byte count, and the gap widens on images with gradients or fine texture. PNG becomes viable too if the source is a screenshot, a diagram or anything with large areas of flat colour, since lossless compression is genuinely efficient on that kind of content.
For photographs, lossless is still the wrong tool even at this size — a full-resolution PNG photo routinely runs several times larger than 20MB with no visible benefit over a good WebP. Use the Auto setting and the tool will pick sensibly based on what you dropped in and how much headroom the target leaves.
Your files never leave the browser
Nothing you drop onto this page leaves your device. The image is decoded, re-encoded and handed back entirely inside the browser tab. There is no upload, no queue, and no temporary copy sitting on someone else's disk waiting for a retention policy to delete it.
That matters more than it sounds. The files people most often need to shrink are the ones they should be most careful with: passport scans, signatures, identity documents, medical forms. Handing those to an unknown server in exchange for a smaller file is a poor trade. Because the work is local, you can shrink a file with the network disconnected and get the same result.
It also means there is no queue to wait in and no daily allowance to run out of. Server-side compressors have to ration free use because every file costs them CPU time; here the CPU is yours, so you can compress image to 20mb as many times as you like, on as many files as you like, without an account.