Resize PNG Images Online — by Pixels or Percentage
Drop a PNG, set the new width or height (or a scale percentage), and download the resized file. Resizing runs entirely in your browser using the Canvas API — your image is never uploaded, and the alpha channel is preserved.
Up to 50 MB · 32,767 px max per side (Chrome / Firefox) · Last verified 2026-04-27
Upload your images
Drag & drop anywhere or click to browse properties.
Supports PNG, JPG, WebP, BMP, TIFF, SVG
How to Resize a PNG
Drop a PNG
Drag and drop your PNG, or click Choose File to browse.
Set Dimensions
Enter a target width or height in pixels (e.g. 1200), or a scale percentage (e.g. 50%). Keep aspect ratio locked so the other side is computed automatically.
Download
Click Resize & Download. The output stays a PNG, with the alpha channel intact.
Verifiably Private
Resizing runs in your browser via the Canvas API. There is no server upload — open DevTools → Network and you will see zero requests during a resize.
Aspect-Ratio Lock
When locked, changing one dimension recomputes the other from the original ratio so circles stay circles and logos stay proportional.
Alpha Channel Preserved
The 8-bit alpha is interpolated together with RGB, so semi-transparent edges scale cleanly. On logos, prefer downscaling to keep edges crisp.
Resize, Compress, Convert, or Crop?
These four operations solve different problems. Pick the right one before reaching for a tool — combining the wrong two wastes quality.
| Goal | Do this | Tool |
|---|---|---|
| Image is the wrong dimensions | Resize | This tool |
| Right dimensions, file too big | Compress | Compress PNG |
| Photographic content, want smaller file | Convert format | PNG → WebP |
| Aspect ratio is wrong | Crop, then resize | Crop PNG |
| Need many sizes (icon set) | Resize to each preset | This tool |
Common PNG Resize Dimensions
| Use case | Width | Height | Recommended PNG variant |
|---|---|---|---|
| Website hero image | 1920 px | 1080 px | PNG-24 (no transparency) |
| Blog / Open Graph share | 1200 px | 630 px | PNG-24 |
| App icon | 512 px | 512 px | PNG-32 (with alpha) |
| Thumbnail | 150 px | 150 px | PNG-8 indexed (UI) or PNG-32 |
When NOT to Resize a PNG
Resizing is the wrong fix for these four cases:
- Don't upscale a screenshot for print. Pixels are interpolated, not recovered. Recreate the asset at the target resolution instead.
- Don't resize a PNG-8 indexed file blindly. The palette mapping degrades on scale; re-export from the source or convert to PNG-24 first.
- Don't resize an icon spritesheet. Scale the source SVG and re-rasterize — never resample a sheet of small UI elements.
- Don't downscale an anti-aliased logo to under 16 px. Edges blur. Use a hand-tuned small-size variant instead.
Verify Privacy in DevTools
- Open DevTools (F12 or Cmd + Opt + I).
- Switch to the Network tab and filter by Fetch/XHR.
- Drop a PNG into the tool above and click Resize & Download.
- You should see zero requests originating from the resize action — the file stays in your browser.
Resize Tips
- Always lock the aspect ratio unless you intentionally want to stretch the image.
- A 50% resize in both dimensions removes ~75% of pixel data — a 4000×3000 PNG becomes 1000×750 = ~1.1 M pixels (vs 12 M).
- For HiDPI / Retina screens, target 2× the CSS dimensions of the slot you are filling.
Browser Canvas Limits
Because resizing happens on an HTML <canvas>, every browser caps the maximum source dimensions. If your PNG exceeds these limits the tool cannot draw it.
| Browser | Max dimension per side | Practical max area |
|---|---|---|
| Chrome / Edge | 32,767 px | ~268 M px |
| Firefox | 32,767 px | ~124 M px |
| Safari (desktop) | 16,384 px | ~67 M px |
| Safari (iOS) | 16,384 px | 16–67 M px (RAM-dependent) |
Frequently Asked Questions
Does resizing a PNG reduce image quality?
Downscaling a PNG generally preserves perceived quality because each output pixel is averaged from multiple source pixels (bicubic-class interpolation). Upscaling cannot recover detail — interpolation invents pixels, so edges look softer. Rule of thumb: never upscale a PNG you intend to print or zoom into; always downscale from the largest available source.
What is the difference between resizing and compressing a PNG, and which should I do first?
Resizing changes the pixel dimensions; compressing keeps the dimensions but re-encodes the pixel data using PNG’s Deflate algorithm. Always resize first, then compress — removing pixels reduces file size far more than compression alone. Once dimensions are correct, run the result through Compress PNG for additional savings.
Is transparency preserved when resizing?
Yes. The 8-bit alpha channel is interpolated alongside the RGB channels, so semi-transparent pixels scale cleanly. On logos and icons, prefer downscaling over upscaling to avoid soft edges and slight halo artifacts at semi-transparent borders.
Can I resize by percentage?
Yes. Switch to percentage mode and enter a value such as 50%. Both width and height scale proportionally. You can also enter exact pixel values in pixel mode.
Does the output stay a PNG?
By default the resized file is still a PNG with the alpha channel preserved. If your goal is a smaller file rather than smaller dimensions, convert to WebP or AVIF — see the related tools below.
Related Tools
- Compress PNG keep dimensions, shrink the file.
- Crop PNG change shape, not size.
- Remove Background transparent cut-out.
- PNG to JPG drop alpha for photographs.
- PNG to WebP modern, smaller-than-PNG format.
- JPG to PNG gain alpha support.