🎯 Compress to Size

Step-by-step

1. Choose your images Drag them in or click to select — several at once is fine. Each image gets its own quality level worked out; they do not all share one setting.
2. Enter the target size Type the number you have to stay under. A form saying "2MB max" means 2 with MB selected; "under 500KB" means 500 with KB. The result is guaranteed to come in below it, not right on the line.
3. Pick the output format Use JPG if you are not sure — it has the best compatibility. If the receiving system accepts WebP, it holds noticeably more quality at the same target size.
4. Decide about resizing Leave it on. Some images exceed the target even at the quality floor, and shrinking dimensions is the only way down. With it off, the tool gets as close as it can and tells you how far off it landed.
5. Run it and download You are told what quality it settled on and whether it had to resize. The filename carries the target, e.g. photo-2048kb.jpg.

When you would use this

Why this needs its own tool

A normal compressor works one way: you give it a quality level, it gives you a file size. Real requirements usually run in the opposite direction — the form says "2MB maximum", the corporate mailbox rejects anything over 10MB, the marketplace caps product images at 500KB. What you want is not "80% quality", it is "under this number, and as good as possible".

Doing that by hand means dragging a slider, checking the size, still too big, dragging again — three or four attempts per image, forty for ten images. This tool automates the loop, and searches per image, so one unusually large photo does not drag the quality of the whole batch down.

What it actually does

The core is a binary search. With a quality floor of 40% and a ceiling of 95%, the first attempt encodes at 67.5%:

• Under the target → there is headroom, search upward (and remember this passing result)
• Over the target → too ambitious, search downward

Each round halves the range, so 8 rounds narrow 55 percentage points to under 0.2. It also stops early once a result reaches 93% of the ceiling — squeezing closer than that buys the user nothing and only costs more encoding time.

When even minimum quality is too big

This happens more often than you would think. A 4000×3000 photo compressed to 200KB is fighting its own pixel count: no reasonable quality level will get it there. The only remaining lever is dimensions.

With "allow resizing" on, the tool shrinks to 0.8× (about 64% of the area) once quality bottoms out and searches again, up to 6 times. In practice one or two rounds usually clear it — and the quality you buy by resizing generally looks far better than the quality you lose by over-compressing. A sharp 2000px photo beats a 4000px one riddled with artefacts every time.

JPG or WebP

If the receiving system takes WebP, choose it. At the same target size WebP retains noticeably more detail, which means the search can stop at a higher quality level. Just confirm it is accepted first — a great many upload fields still recognise only .jpg and .png.

Frequently asked questions

What you might need next

Image work rarely ends in one step. These pair up with Compress to Size most often:

• 🗜️ Compress Image — Shrink file size while keeping quality
• 📐 Resize Image — By width, percentage, or exact size
• 🖼️ Convert to JPG — PNG, GIF, and WebP to JPG

Want to share the result? Upload turns images, photos, or videos into a short link with optional password, expiry, and view limits. Or head back to all 12 tools.