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Start with the part most comparison pages leave out
TinyPNG’s compression is genuinely strong. It runs a quantiser: it reduces a PNG’s full colour range to a carefully chosen smaller palette, which is what produces those very large savings on flat graphics and screenshots. That is real engineering and it is better at that specific job than a browser canvas is.
So if the only thing you care about is the smallest possible PNG, and the image is not sensitive, use TinyPNG. We would rather tell you that than have you find out.
What this site does differently
Two things, and neither is “compresses harder”:
- The image never leaves your device. No upload, no API key, no monthly allowance to track. For product photos that is irrelevant; for screenshots of internal dashboards, unreleased designs, documents or anything under an NDA, it is the whole question.
- Format conversion is part of the job. Converting a PNG to WebP usually beats quantising it as a PNG — often by a wide margin, and with no palette reduction at all. If the target is a website, that is normally the better move, and it happens in the same step here.
There is also no limit on how many images you process, because there is no server-side cost to meter.
Which to reach for
| Your situation | Better choice |
|---|---|
| Smallest possible PNG, image not sensitive | TinyPNG’s quantiser |
| Screenshot of internal or confidential work | This page — it is never transmitted |
| Images for a website | Convert to WebP here — usually smaller than a quantised PNG |
| Photographs (JPEG) | Either; the gap is much narrower on photos |
| Hundreds of files, offline | This page — no quota, works with the network off |
| Automated build pipeline | An API — this is a site a person uses, not a service |
What actually happens to the file here
The image is decoded in your browser, re-encoded at the quality and format you choose, and handed back as a download. JPEG quality is a real quality setting, not a fixed preset. PNG output is re-encoded losslessly — and when that would produce a larger file than the original, which is a normal outcome for an already-optimised PNG, the original is kept instead. A “compressor” that hands back a bigger file is a bug, not a result.
Metadata is worth a separate thought: photographs carry GPS coordinates and camera serial numbers, and compressing an image does not necessarily remove them. If the picture is going onto the public web, run it through Remove EXIF Metadata as well.
How to compress an image without uploading it
Step 1: Add your images
Drag one or many onto the box above. A batch comes back as a ZIP.
Step 2: Choose format and quality
WebP for the web, JPEG for photographs, PNG to stay lossless. The quality slider is a real encoder setting.
Step 3: Compare before and after
You get both file sizes and a slider to check the result at full size before you commit to it.
Step 4: Download
The compressed file saves straight to your device. Nothing was transmitted at any point.
Frequently Asked Questions
Does this compress as well as TinyPNG?
On flat-colour PNGs, usually not — their quantiser is stronger at that one job. On photographs the gap is small, and converting to WebP here often beats a quantised PNG outright.
Is there a monthly limit?
No. Nothing is counted, because nothing is processed on a server that would cost us anything to run.
Are my images uploaded?
No. Compression happens in your browser; the project contains no API route that accepts a file.
Does compressing remove EXIF and GPS data?
Do not rely on it. Re-encoding drops some metadata, but if privacy is the goal, use Remove EXIF Metadata, which is built to do exactly that and shows you what it found first.
Is there an API?
No. There is no server, so there is nothing to call. For a build pipeline, use a local library or a service that offers one.
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