Free PNG Compressor
Compress PNG graphics
while retaining PNG output.
Re-encode screenshots, interface graphics, and transparent artwork as PNG, with an optional maximum width and honest size comparisons.
- PNG-only validation
- Transparency retained
- No misleading quality slider
PNG Compressor workspace
PNG output retains transparency. This browser workflow does not claim a PNG quality level; resizing changes pixels and dimensions.
Images
Three clear steps
How to use the png compressor
The entire workflow stays in the current browser tab, from selection through download.
Add PNG files
Choose screenshots, graphics, or transparent images. Non-PNG content and animated PNG files are rejected.
Keep or reduce dimensions
Leave the original width unchanged, or choose a smaller maximum width when fewer pixels suit the destination.
Check every result
PNG re-encoding does not guarantee a smaller file, so compare the reported output before downloading.
Where PNG fits
Useful for crisp graphics and alpha transparency
PNG is a lossless image format commonly used when sharp edges, flat colors, or transparent pixels matter more than photographic compression efficiency.
Screenshots and UI details
PNG can preserve crisp text and interface edges that may show artifacts in a lossy photo format.
Logos, diagrams, and flat color
Simple color regions may encode efficiently, while noisy or highly complex imagery can remain large.
Overlays and cutouts
The PNG output keeps its alpha channel instead of placing transparent pixels on a matte.
PNG behavior
Content complexity drives PNG size
Dimensions are only part of the story. The number and arrangement of colors can make two equally sized PNG images compress very differently.
Flat areas and repeated patterns
Graphics with limited color variation can be a good match for PNG compression.
Photos, grain, and complex gradients
Photographic detail creates less repetition, so PNG files can remain much larger than JPEG or WebP alternatives.
Small gains are normal
A carefully optimized source may leave little room for a browser re-encode to reduce size.
Optimization strategy
PNG does not use the JPEG-style quality control
This page keeps PNG output and omits a quality slider because the browser PNG encoder does not expose the same lossy-quality choice. Resizing changes dimensions, so a resized PNG is not a lossless transformation.
Compare rather than assume
A clean browser re-encode can change the byte structure and metadata, but it may produce a larger file.
Reduce pixel dimensions deliberately
Choosing a smaller maximum width can reduce size, but it changes image information and is not a lossless operation.
Inspect edge appearance
Alpha transparency is retained, but resized semi-transparent edges should still be reviewed against their intended background.
Current boundaries
Transparent about PNG limitations
ImagePhix uses the browser canvas encoder rather than a specialized palette optimizer or command-line PNG tool.
- 20 files per batchEach file can be up to 100 MB.
- Up to 64 megapixelsNo side may exceed 16,384 pixels.
- Metadata is not retainedOutputs are newly encoded; keep originals when metadata matters.
- Animated PNG is rejected rather than reduced to one frame.
- JPEG and WebP inputs are rejected; this page does not convert them to PNG.
Questions, answered
PNG Compressor FAQ
Concise answers about the behavior and boundaries of this specific workflow.
Is PNG compression lossless?
PNG is a lossless image format, and ImagePhix retains PNG output. Resizing changes dimensions and pixels, however, and newly encoded output does not retain source metadata.
Does PNG compression preserve transparency?
Yes. ImagePhix retains PNG output and transparent pixels; this page does not apply a matte background.
Why is my PNG file still large?
Noisy, photographic, or otherwise complex images contain less repeated information than many logos and flat-color graphics. The source may also be already optimized.
Can I compress multiple PNG files at once?
Yes. You can add a batch of PNG screenshots, logos, or graphics, and ImagePhix validates and processes each file locally.
Does resizing a PNG reduce file size?
It often can when the source is larger than the dimensions you need. Resizing removes pixels and changes the image, so it is not a lossless transformation.
Is PNG metadata preserved?
No. The output is newly encoded without preserving source metadata or ancillary chunks. Keep the original when that information matters.
Can a compressed PNG become larger?
Yes. Different encoders make different choices, and a browser re-encode can exceed an already-efficient source. Check the reported output size.
When should I use PNG instead of JPEG or WebP?
PNG often suits screenshots, logos, crisp UI graphics, and images where lossless pixels or transparency matter. JPEG often suits photos, while WebP can be useful for efficient web images.
Back to the tool
Ready to check a PNG re-encode?
Return to the PNG workspace and compare the result before deciding whether to save it.