Compress Image to an Exact KB Size
Upload limits usually demand a specific file size — 100KB for a marketplace, 50KB for an email, 20KB for a government form. These tools binary-search quality until your image fits the exact target, right in your browser. No uploading, no watermarks, no signup.
Choose your format below. Not sure? JPEG for photos, PNG for screenshots and logos, WebP for the web, AVIF for maximum compression.
Compress any image to 20KB
Strictest limit — form uploads and portals. Expect dimension reduction for photos.
Compress any image to 50KB
Email attachments, chat profile pictures, job portals.
Compress any image to 100KB
The most common target — blog images, marketplace listings, CMS uploads.
Compress any image to 200KB
Hero images and portfolio shots with room for high quality.
Compress any image to 500KB
High-resolution photography and banners that stay shareable.
How exact-size compression works
Every tool on this page uses a binary search over encoder quality: it compresses at the midpoint quality, measures the result, and halves the search range — about 12 iterations to land within a few bytes of your target. The full image is processed locally with WebAssembly-grade canvas encoders, which is why there is no upload wait and no file limit.
Which format should I pick?
- JPEG — smallest universal option for photos; accepted everywhere.
- PNG — lossless with transparency; quantization keeps text and edges sharp.
- WebP — 25–35% smaller than JPEG at the same quality; accepted by most modern sites.
- AVIF — the compression leader, roughly half the size of JPEG; newest browsers support it.
How to compress an image to a specific size — 3 steps
- Pick your output format — JPEG for forms and uploads, PNG for screenshots with text, WebP or AVIF when the site accepts modern formats.
- Drop your image into the tool — it starts compressing instantly, right in your browser.
- Download the result — the filename tells you the exact target, e.g.
photo-100kb.jpg.
Common upload size limits
Most “file too large” rejections come from a handful of well-known limits. Match yours below:
| Use case | Typical limit | Recommended tool |
|---|---|---|
| Government / exam form photo | 20–50KB | JPEG → 20KB |
| Signature image | 10–20KB | JPEG → 20KB (custom target) |
| Profile picture / avatar | 50KB | JPEG → 50KB |
| Marketplace / listing photo | 100KB | JPEG → 100KB |
| Blog / CMS upload | 100–200KB | WebP → 100KB |
| Hero / banner image | 200–500KB | AVIF → 200KB |
| Email attachment | 500KB–1MB | JPEG → 500KB |
Free online JPEG compressor — no limits
If you don’t need an exact size, the JPEG compressor reduces file size with a simple quality slider — no KB target required. It runs on the same local engine as the tools above, so nothing is uploaded. For other formats there are dedicated PNG compressor (with palette quantization for screenshots), AVIF compressor, and a general photo compressor that keeps family photos looking natural. Working with a whole folder? The bulk compressor handles batches in one pass.
Custom targets: 10KB, 30KB, 40KB and beyond
The preset pages cover the most requested sizes, but every tool accepts any target from 1KB up. Open a tool, switch the Target Size field to your exact limit — 10KB for forum avatars and signature images, 30KB for messaging apps, 40KB for job-portal uploads, 1MB for print-quality proofs — and the same binary search lands you under the limit.
Frequently asked questions
How do I compress an image to exactly 100KB?
Open the JPEG to 100KB tool (or pick PNG, WebP, AVIF), drop your image, and the tool binary-searches encoder quality until the output fits within 100KB — usually in under a second, entirely in your browser.
What if my target is 10KB, 30KB or 40KB?
Every tool on this page has a Target Size field you can set to any value from 1KB upward — 10KB for forum avatars, 30KB for signature images, 40KB for messaging apps. The binary search works the same way for any target.
Which format gives the smallest file size?
AVIF is typically the smallest (about half of JPEG at similar quality), followed by WebP (25–35% smaller than JPEG). JPEG is the safest universal choice since every website and form accepts it.
Will compressing to a smaller size ruin image quality?
The tools find the highest quality that still fits your target, so quality drops only as much as physically necessary. For very small targets like 20KB on a large photo, resolution is effectively the limit — try WebP or AVIF for noticeably better results.
Are my images uploaded to a server?
No. All compression runs locally in your browser via canvas and WebAssembly encoders. Images never leave your device.
How do I compress a JPEG to 20KB for a government form?
Open the JPEG to 20KB tool, drop your photo, and download the result — it lands under 20KB automatically. For forms that also need a signature image, the same tool accepts any custom target such as 10KB or 30KB.
Can I compress multiple images to the same size at once?
Yes — the bulk compressor processes a whole batch with the same quality settings, and every file is still handled locally in your browser.
What's the difference between compressing and resizing?
Compressing reduces file size while keeping dimensions (via smarter encoding or fewer colors). Resizing changes pixel dimensions. For strict KB limits, compress first; if the target is very small, combining both works best.
More compression tools
Converting between formats before compressing can shrink files dramatically — HEIC to JPEG for iPhone photos, or the compression ratio analyzer to see exactly where the bytes go.
Privacy first
Your images never leave your device. Compression happens entirely in your browser using client-side encoding — nothing is uploaded, stored, or logged.