What changes
Lossy encoding can soften detail. The tool may also reduce pixel dimensions to reach the target, even when starting at the original size. Neither unchanged dimensions nor a smaller output is guaranteed.
Compress image to a target KB size
Compress JPG, PNG and WebP images to a target file size privately in your browser.
Runs locallyNo uploadYou control saved copies
1 Choose image2 Set size3 Download
Compression can reduce pixel dimensions to reach the KB target, even when starting at the original size. Check final dimensions and clarity. Changing these settings does not update an existing result until you compress again.
Processing happens in this browser. Nothing is uploaded.
Compress an image to a KB limit
Use this when a form rejects a photo because its file size is too large. The browser searches for the clearest JPEG or WebP quality that stays at or below your selected KB ceiling.
For a reliable result
- Choose a supported image and confirm its dimensions.
- Enter the maximum KB accepted by the destination form.
- Compare the local preview, then download only if important details remain clear.
Check the download
Check faces, signatures, printed numbers, final dimensions and Target status. The target is a ceiling, not an exact file size; compare the output with the original as well.
Know before processing
Very noisy photographs may not fit an extremely small target without visible quality loss. Try resizing first when the pixel dimensions are much larger than required.
Quick answers
- Will the image be exactly the KB size I enter?
- No. The number is a maximum, so a successful result can be smaller. The tool keeps the clearest candidate that stays at or below that ceiling.
- Why can a very small target look softer?
- JPEG and WebP compression remove detail to save bytes. Fine hair, printed text and noisy backgrounds show that loss first, so resize oversized images before choosing an extreme target.
Meet an image byte ceiling without overlooking dimensions
Use this tool when an upload has a maximum file size. It re-encodes an image as JPG or WebP, searches bounded quality settings and can reduce the dimensions if quality changes alone do not meet the target. The source remains unchanged.
A smaller file is useful only if it still satisfies the destination's other requirements. Check minimum pixel dimensions, permitted format and readability alongside bytes. Maximum dimension is a starting cap on the longest edge, not an exact output size or a promise that later compression will preserve that edge.
Separate the upload's different constraints
| Your situation | Recommended approach |
|---|---|
| Only a maximum KB value is specified | Enter that ceiling and start without an initial dimension cap. Inspect the actual result because the search can shrink dimensions to meet the target. |
| The image is much larger than its intended display | Choose a Maximum dimension such as 800 px. This caps the longest edge while preserving proportions and does not enlarge a smaller source. |
| Exact or minimum pixel dimensions are mandatory | Check the final Dimensions value before submission. A byte-compliant result that has become too small is unsuitable; this tool does not lock dimensions during target searching. |
| The destination needs transparency | Try WebP only if it is accepted by the destination. JPG fills transparent areas with white. Neither format is guaranteed to be the smaller suitable choice for every image. |
Compress a textured sample toward 100 KB
The textured-image.png sample is a deterministic 1200 × 800 synthetic image. Its texture gives the encoder more detail to handle than a plain colour block without exposing a personal photograph.
- Choose textured-image.png and select the 100 KB preset.
- Set Maximum dimension to 800 px and Output format to JPG.
- Select Compress image. Confirm Target ceiling is 100 KB and read Target status: Met or Not reached. A download alone does not demonstrate success.
- Read Compressed and Dimensions, then open the JPG. Compare the texture and sharp edges with the source at a matched display size.
Expected result. The initial size is approximately 800 × 533 pixels, preserving the source's proportions with whole-pixel rounding. The search may reduce it further. Here, 100 KB is a ceiling of 102,400 bytes; the actual result shows whether it fit, and its byte size need not equal that number.
Check the downloaded result
- Read Target ceiling, Target status and actual size. These describe the completed run; changing a control does not update it. Select Compress image again to apply new settings.
- Compare final dimensions with any required minimum or exact size. Check those values again after every later edit or conversion.
- Inspect faces, signatures, small text and fine edges at their intended viewing size. Compression artifacts that are invisible in a thumbnail may affect the real use.
- Compare original and output bytes directly. Re-encoding can make an already efficient or small source larger even when the result remains below your chosen ceiling.
Troubleshooting
- The result is smaller in pixels than expected
The bounded search can lower dimensions after quality reduction fails to meet the target, including when no initial dimension cap was selected.
Try this: Try a higher ceiling if allowed and compare final dimensions. If the destination requires an exact size, do not submit a smaller result solely because its bytes fit.
- The best attempt still exceeds the ceiling
The allowed quality and resizing attempts ended without producing a candidate below the requested maximum.
Try this: Try another accepted format, remove unnecessary image area in an editor, or use a larger ceiling when permitted. Recheck detail and dimensions after each change.
- Fine text or edges look damaged
Lossy encoding and downsampling discard detail; an extremely tight target can damage the information you need to preserve.
Try this: Return to the original and relax the target if possible. Avoid repeatedly recompressing a degraded download, because additional passes cannot recover the missing detail.
- The browser cannot read a HEIC image
The file picker accepts HEIC/HEIF, but this page's decoding path still depends on browser support.
Try this: Use Image converter to prepare a supported JPG, PNG or WebP, then retry. Confirm the converted source opens correctly before starting compression.
Limits and compatibility
- Targets and formats
- The target range is 10–5,000 KB, with common presets and JPG or WebP output. The search is lossy and bounded; it does not guarantee exact bytes, preserved dimensions or acceptable quality at every target.
- Local processing
- Device limits apply to files, source pixels and memory. Processing uses a worker or browser compatibility path without uploading the image or overwriting its source.
Your files and form values are processed on this device. Downloaded copies remain wherever you save them. See how to check local processing and our privacy policy for site data and optional services.
Common questions
- Why is the file below, rather than exactly at, my target?
- The value is a maximum. The encoder selects a candidate within that ceiling; it does not pad the file to make the bytes equal the target.
- Will a larger target sharpen an already compressed image?
- No. A more generous target can preserve more of the input's remaining detail, but cannot reconstruct pixels discarded earlier. Start from the original whenever possible.
Continue your document workflow
Maintained by Shakti Prasad Ram. Found a mismatch? Report the tool, browser and steps without sending a sensitive document. Back to the tool