CompressPictureCompress an image
Every re-encode happens on this device. No file is posted anywhere.

Reduce image resolution

Fewer pixels — by long edge, percent or megapixels — and the bytes that saves, measured after every change.

Drop a picture. It is re-encoded the moment it opens, and the result is measured, not estimated.Drop, click or paste. One picture opens the tuner; a folder opens the ledger, where every file gets its own quality.
In —Out —Saved —

Nothing to hand?

Nothing leaves this tab: the file is decoded, re-encoded and measured by this page on this device.

When the pixel count is the problem

A 48-megapixel phone photograph is large because it holds 48 million pixels. Lowering the quality spends detail on every one of them and still leaves a big file; reducing the pixel count removes the cost at its source. This page makes dimensions the goal: choose the size, then the quality those pixels are written at, and read the bytes.

  • Long edge: the longer side to a number of pixels, the other side in proportion.
  • Percent: each side scaled by the same share — 50% leaves a quarter of the pixels.
  • Megapixels: a total pixel budget, with the shape kept.
  • W × H and physical sizes are here too, with crop or pad when the shape differs.

Fewer pixels cannot be undone.

Detail removed by a resize does not come back by enlarging later. Keep the original; the download is a new file named after it.

Questions people arrive with

Does reducing resolution make the file smaller?
Almost always, and by more than quality alone can. File size runs roughly with pixel count: halving each side leaves a quarter of the pixels. The size on the ruler is measured after every change, so you see the real figure rather than an estimate.
Is resolution the same as DPI?
No. Resolution here means pixel dimensions — 4032 × 3024, say. DPI is a number in the header that says how large those pixels should print; changing it moves no pixel and saves no byte. Where a form asks for a DPI, the photo resizer in KB writes it.
Which long edge should I pick?
1920 px fills a laptop screen; 1080 px is what most social feeds keep; 1600 px is plenty for a chat app that recompresses anyway. Only edges smaller than your picture are offered, because this page never enlarges.
Which resampler is used?
The browser's own high-quality canvas resampling, in a background worker. A dedicated Lanczos pass is planned; until then the page does not claim one.

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