Compress JPEG to 100 KB
Compress a JPEG file to under 100 KB, keeping JPEG as the output format.
Finding the best quality that fits…
- Original
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- Result
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- Reduction
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- Dimensions
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How to use this tool
- Select your file, drag it onto the box above, or paste it from your clipboard.
- Processing starts automatically — there is nothing to configure.
- Check the result panel, which shows the original size, the final size and the output dimensions.
- Click Download to save it.
JPEG is the right format for photographs and reaches small sizes efficiently. The tool searches quality levels to land just under 100 KB.
The specification
| Target file size | Under 100 KB |
|---|---|
| Output format | JPEG |
| Method | Binary search over JPEG quality |
| Transparency | Flattened onto white |
Why uploads get rejected
Meeting the size is only part of it. These are the failures that actually come up:
- The source was a PNG screenshot converted to JPEG — text and sharp edges pick up visible artefacts. For screenshots, keep PNG.
- The image was already heavily compressed, so re-compressing degrades it further.
- The dimensions are large enough that 100 KB forces heavy quality loss. Reduce the dimensions first.
How it works
Most compressors pick a fixed quality level and hope for the best, which is why they either overshoot the limit or land far below it and throw away detail you did not need to lose.
This tool runs a binary search instead. It encodes your image at a mid-range quality, measures the resulting file, then narrows the range — higher if there is room, lower if it is over — repeating seven times. It keeps the largest result that still fits. If the lowest quality is still too big, it reduces the pixel dimensions and searches again.
All of it runs on your own device using the browser's canvas API. Nothing is transmitted.
Who uses this
Situations where the output format is fixed — a form that accepts only JPEG, or a workflow where the format must not change.
Frequently asked questions
Why keep JPEG rather than convert?
JPEG is the most widely accepted format on upload forms and the most efficient for photographs. Keeping the format avoids compatibility surprises.
How does the quality search work?
It encodes at a mid-range quality, measures the file, and narrows the range seven times, keeping the largest result under 100 KB.
Will the quality drop?
Some quality is always lost when a file gets smaller — that is what compression means. The tool searches for the highest quality that still fits under your limit, so it gives up as little as possible.
Are my files uploaded to a server?
No. Everything runs inside your browser on your own device. Your file is never transmitted and never stored by us. You can confirm this by opening your browser’s Network tab while you use the tool — you will see no upload request.
Is there a limit on how many files I can process?
No. There is no daily cap, no account, and no watermark. Because the work happens on your device rather than our servers, there is nothing for us to ration.
Is this tool really free?
Yes — no account, no trial, no watermark, and no cap on usage. It runs on your own device rather than our servers, so there is no cost for us to pass on.
Does it work on mobile?
Yes. The interface adapts to phone and tablet screens, and everything runs in the browser, so there is no app to install.
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Your files stay on your device. This tool runs entirely in your browser. No file is uploaded, transmitted, or stored. You can verify this by opening your browser's Network tab while using the tool.
Disclaimer. Specifications published by exam boards, governments and platforms change without notice. We verify and date every specification on this site, but you should always confirm against the official source before submitting an application. See our full disclaimer.