IMG / 01 · exact-size compression
Compress image to 100 KB
100 KB is the first size where a photograph stops looking compressed. It is the working budget for a thumbnail, a profile picture, a product grid image or an avatar — anywhere an image appears small and appears many times. At typical thumbnail dimensions it is effectively lossless; at full page width it still asks you to give something up.
Zooly is still building this one. The interface below is the real thing, switched off until the compression engine ships. Nothing here will accept a file yet — we would rather show you what is coming than fake a progress bar. Read how it will work.
- 1 Choose
- 2 Compress
- 3 Download
No upload · processed on device · metadata stripped
How to compress an image to 100 KB
- 01
Choose your image
Drop a file on the tool or press the button to pick one. Because nothing uploads, a large file costs you no waiting — a 40 MB camera JPEG starts processing as fast as a screenshot.
- 02
Set the target
Pick a preset or type an exact number in KB or MB. This is a ceiling, not a goal: the result will be at or under it, never over.
- 03
Let the search run
The tool encodes at several quality levels and narrows in on the highest one that still fits, rather than encoding once at a guessed setting. On Auto, dimensions are only reduced if no quality level can reach the target.
- 04
Check and download
You see the original size, the new size and the reduction as a percentage, with a preview to judge the result. Aspect ratio is preserved and camera metadata is dropped.
What 100 KB realistically holds
This is the size most often chosen rather than imposed. If you are picking a per-image budget for a listing page or a gallery, 100 KB is a defensible default that keeps a grid of twenty images under 2 MB.
| Image type | At 100 KB | Notes |
|---|---|---|
| Passport-style headshot, 600 px wide | Comfortable | Effectively lossless at this resolution |
| Screenshot of text or UI | Workable | Readable at moderate size; PNG is still better for pure text |
| Detailed landscape photo, full width | Tight | Acceptable up to about 1200 px wide, soft beyond it |
| Flat logo or icon | Comfortable | Far more room than needed |
Guidance from typical JPEG behaviour at common web resolutions, not measured benchmarks. Published test data is on the roadmap, and we will say so here when it exists.
Privacy
Your image is decoded, compressed and re-encoded inside this browser tab. It is never sent to ToolZool or to anyone else, there is no upload queue, and nothing is stored — which is also why we cannot see what you processed.
- No upload — there is no endpoint to send a file to
- Nothing stored, so there is nothing for us to delete or leak
- Camera, timestamp and GPS metadata are dropped by re-encoding
- Works offline once the page has been visited
Supported formats
Accepts
JPGPNGWebPAVIF
Produces
JPEGWebP
Practically around 50 MB in a normal browser tab. The limit is your device's memory, not a server quota.
Who uses this
Students and applicants
A portal that will only accept 50 KB. Exam boards, visa forms and job sites cap uploads. Set the number, keep the face recognisable.
Site owners
Images that do not wreck page speed. Hit a per-image budget before upload, so Core Web Vitals stay green without a build step.
Office and admin
A photo too big to email. Bring an attachment under the limit without opening desktop software.
Anyone with a phone
Huge camera files. Modern phone cameras produce 10–20 MB images that most forms simply refuse.
Limitations
- Compression is lossy. If your original is far above the target, some quality loss is unavoidable — the tool minimises it, it cannot eliminate it.
- Screenshots of text and UI compress badly as JPEG. Below roughly 100 KB they go visibly soft; reducing dimensions usually looks better than pushing quality down.
- Re-compressing an already-compressed file compounds the loss. Work from the original whenever you have it.
- Very large files are bounded by your device's memory rather than by any quota we set. On a phone, expect trouble well before 50 MB.
- Animated GIFs and multi-frame images are not supported; the first frame would be all that survived.
Other exact targets
Every size has a different answer to "will my image survive this". Pick the one you were actually given.
Questions about this tool
Is 100 KB small enough for good page speed?
For a thumbnail or a grid image, comfortably. For a full-width hero it is generous rather than tight. What matters more than any single number is the total weight of images above the fold — one 100 KB hero is fine, twelve of them is not.
Will the image lose visible quality?
Some, unavoidably, if the original is far above the target. ToolZool minimises it by finding the highest quality that still fits, and reducing dimensions only when quality alone cannot get there.
Which formats can I put in?
JPG, PNG, WebP and AVIF. Output is JPEG or WebP; WebP reaches a given size at better quality, but check the form you are submitting to accepts it.
Is there a file size limit?
Practically around 50 MB in a normal browser tab. The constraint is your device memory rather than a server quota.
Is EXIF and location data removed?
Yes. Re-encoding drops camera, timestamp and GPS metadata. Orientation is applied to the pixels first, so the image does not come out rotated.
Does the result go over my target?
No. The target is treated as a ceiling. If no setting can reach it — which happens when a target is very small and the image very detailed — the tool tells you the smallest size it managed instead of silently handing you a file that is too big.
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About this tool
Most image compressors give you a quality slider and leave you to guess. That is the wrong way round, because the constraint you were handed is a number: 50 KB for an exam portal, 2 MB for an email attachment, 500 KB for a page that has to stay fast. This tool works from the number. It searches encoder quality levels for the highest one whose output still fits under your target, and only reduces dimensions when quality alone cannot get there. You get the largest file that fits — which is also the best-looking one.