Compress PNG
Keep the PNG format while choosing whether pixel changes are acceptable. This page starts with up to 256 colours, a lossy setting. Select Lossless when you want to avoid palette changes to the rendered image, and keep the source as your reference.
Drop your images here
JPG, PNG or WebP · Up to 20 images · 25 MB per image
Or paste an image from your clipboard.
Saved presets
Save batch settings and upload rules on this device. Images are never saved in a preset. Individual image overrides take precedence over batch settings.
Upload requirements checker
Copy the limits from the website you are uploading to. Checks compare these rules with each original and download; they do not change compression settings. A pass covers only the rules entered here, not the receiving website's other checks.
1 KB = 1,000 bytes. To require exact dimensions, set matching minimums and maximums. This tool never enlarges or crops an image to force a pass.
Targets use decimal KB (1 KB = 1,000 bytes). Quality is the maximum for JPG/WebP; we search for the highest tested quality that fits. PNG has lossless optimisation and optional colour reduction, which may alter colours and soft transparency. PNG mode applies to PNG output only. If it still exceeds your target, allow resizing. Any unmet target is clearly marked. JPG uses a white background. Animated images are not supported.
Choose images to get started.
Preview upload fixes
Candidates are made from your original. Compare them before applying; your current download stays available until you choose a replacement. Only candidates passing every entered rule can be applied.
Compare the detail
Drag to pan, or scroll with a mouse, trackpad or touch. At 100%, one output pixel equals one CSS pixel. The original is aligned to the output dimensions for comparison.
Choose the mode before judging the result
Lossless optimisation encodes the rendered pixels without a palette-reduction step. That is narrower than preserving the entire original file: decoding, colour handling, metadata and any selected resizing are separate concerns. If an unchanged file or archival master is required, retain the original.
Palette modes allow up to 256, 128 or 64 colours. Merging colours may save bytes, but it can introduce bands in gradients, alter a logo’s colour and change semi-transparent edges. Fewer colours are not automatically suitable for every screenshot or graphic.
A practical PNG comparison
- Add a still PNG and confirm Output format is PNG. A saved preset or per-image override can change the page defaults.
- Try Lossless with no resizing to establish a rendered-pixel baseline. Record whether the original was kept because it was already smaller.
- Try up to 256 colours from the same source. Inspect text edges, gradients, shadows and important colour areas.
- Compare a lower palette only if the first result is acceptable. Check at the intended display size as well as enlarged zoom.
- Download the chosen file and view it against the backgrounds where it will actually be used.
The comparison aligns the original to output dimensions. When you also resize, inspect the source separately to understand the detail removed by scaling. A transparent edge that seems fine on white may reveal a fringe on a dark page.
Worked example: judge bytes and appearance together
If a 240,000-byte PNG becomes 180,000 bytes, the saving is 25%. If a palette version becomes 90,000 bytes, that is a 62.5% saving from the same source. These are illustrative calculations, not promised results. The smaller version may still be the wrong choice if a required colour or thin line has changed.
The JPG/WebP quality slider does not control PNG compression. For a PNG size target, choose its PNG mode and decide whether smaller dimensions are permitted. The tool does not guarantee that it can meet every target without an unacceptable change.
Know when a format change is worth comparing
A photograph stored as PNG may be a candidate for JPG if transparency is unnecessary and lossy output is allowed. WebP can be another option for web delivery with transparency. Neither guarantees a smaller acceptable result; compare actual bytes and detail, and confirm destination support.
Keep PNG when a workflow requires it or when its lossless rendered output suits the image. Use PNG to WebP for a delivery-copy comparison rather than replacing your only source.
Transparency, metadata and large outputs
PNG supports an alpha channel. Lossless output preserves rendered alpha values when the picture is otherwise unchanged; palette reduction and resizing can change edge appearance. This tool does not guarantee an identical colour-managed or metadata-complete file.
Advanced PNG processing is limited to 16 million output pixels. Larger lossless outputs use the browser encoder, while palette-reduced output needs smaller dimensions. Animated PNG is rejected. When the original is retained instead of re-encoded, its metadata remains; do not assume compression removed private information.
Related image tasks
Common questions
Is the default PNG mode lossless?
No. This page initially selects up to 256 colours, which is lossy. Select Lossless explicitly to avoid palette reduction.
Will transparency look exactly the same?
Do not assume that for palette-reduced or resized output. Check soft edges and shadows on the intended backgrounds.
Why does the quality slider not shrink my PNG?
That control applies to JPG and WebP. PNG output uses the PNG compression mode and any chosen dimension or size settings.
Does PNG compression always remove metadata?
No. An unchanged original may be retained. Re-encoding changes the file structure, but this tool is not a certified metadata-removal service.
Content reviewed by eToolPlus · 16 October 2026