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Convert PNG to WebP free, without uploading
PNG to WebP shrank our 1281×1600 px test portrait from 4.46 MB to 141 KB (−97%). Quality stays high unless you set a KB limit. Drop the PNG (.png) on the tool below and download the WebP; nothing is uploaded.
PNG to WebP
WebP · no file-size limit · original pixel size
No file-size limit is set: PixelFit saves at high quality and changes only the format and any pixel size you set.
Fit, background and padding white background
Saving presets is part of Pro.
The result appears here: the exact byte count, pixel size and quality, the size before and after, a preview and a download button.
The batch kit (one ZIP for up to 500 photos, several photos merged into one PDF) is part of Pro.
What changes from PNG to WebP
5 of these 6 points lose or alter something on the way from PNG to WebP; the rest carry over.
- Kept: Transparency survives: WebP keeps the alpha channel of the PNG.
- Lost or changed: Animated PNGs (APNG) are rare, but if yours is one, only its first frame becomes the WebP.
- Lost or changed: WebP is lossy: the exact pixels of the PNG are approximated, which is invisible on photos at high quality but can blur sharp text and edges.
- Lost or changed: PNG can hold more than 8 bits per channel (1 to 16 bits per channel); a browser canvas works at 8 bits, so 10-, 12- or 16-bit files are reduced to 8 bits per channel.
- Lost or changed: Metadata is not carried over: the PNG's text chunks, eXIf and ICC data are dropped by the canvas.
- Lost or changed: WebP allows at most 16,383 pixels per side, so larger images have to be scaled down to fit.
Measured file size: PNG vs WebP
sharp 0.35.5 / libvips 8.18.7, 31 October 2026, long edge 1600 px; WebP saved as quality 85, alpha kept, PNG as lossless, zlib level 6, RGBA.
| Sample | PNG | WebP | Change |
|---|---|---|---|
| portrait photo (1281×1600 px) | 4.46 MB (4,679,548 bytes) | 141 KB (144,388 bytes) | −97% |
| landscape photo (1600×1200 px) | 4.74 MB (4,972,383 bytes) | 587 KB (600,728 bytes) | −88% |
| scanned typed letter (1273×1600 px) | 2.59 MB (2,714,410 bytes) | 199 KB (203,570 bytes) | −93% |
| flat chart with a transparent background (1600×1000 px) | 39.7 KB (40,653 bytes) | 14.1 KB (14,418 bytes) | −65% |
What the numbers mean for PNG to WebP
Our portrait photo at 1281×1600 px: PNG 4.46 MB → WebP 141 KB (−97%, 32.4 times smaller).
Our landscape photo at 1600×1200 px: PNG 4.74 MB → WebP 587 KB (−88%, 8.3 times smaller).
Our scanned typed letter at 1273×1600 px: PNG 2.59 MB → WebP 199 KB (−93%, 13.3 times smaller).
Our flat chart with a transparent background at 1600×1000 px: PNG 39.7 KB → WebP 14.1 KB (−65%, 2.8 times smaller).
Per pixel, the portrait took 18.27 bits as PNG and 0.56 bits as WebP, a difference of 4.33 MB on 2,049,600 pixels.
Per pixel, the chart took 0.20 bits as PNG and 0.07 bits as WebP, a difference of 25.6 KB on 1,600,000 pixels.
WebP came out smaller than PNG on all 4 samples, from −65% to −97%.
For comparison, the original portrait saved directly as a quality 85 JPG was 254 KB and as a quality 85 WebP 141 KB, −44% against the JPG.
How to convert PNG to WebP
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Add the PNG file
Drop the .png file on the tool at the top of this page, tap to choose it, or paste it.
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Keep WebP selected
WebP is pre-selected at quality 85. Type a maximum size in KB or exact pixel dimensions only if the destination sets them; PixelFit then searches the highest quality that fits and shrinks the pixel size only when quality alone is not enough. Our PNG test portrait came out at 141 KB as WebP with no limit set.
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Download the WebP
Save the file ending in .webp; its size in KB shows before you save.
PNG and WebP side by side
PNG (1996) next to WebP (2010); browser figures checked 31 October 2026.
| Property | PNG | WebP |
|---|---|---|
| File extensions | .png | .webp |
| MIME type | image/png | image/webp |
| Compression | lossless | lossy or lossless |
| Transparency | yes | yes |
| Animation | yes | yes |
| Largest size | 2,147,483,647 px per side | 16,383 px per side |
| Colour depth | 1 to 16 bits per channel | 8 bits per channel |
| Metadata | text chunks, eXIf and ICC data | EXIF, XMP and ICC chunks |
| First published | 1996 | 2010 |
| Opens in | Chrome, Edge, Firefox, Safari (every current browser); about 97.49% of browsers in use | Chrome 32+, Edge 18+, Firefox 65+, Safari 16+ (Safari 14-15 only on macOS 11 or later); about 97.08% of browsers in use |
| Good for | screenshots, logos, signatures on white and images with transparency | web pages, where it is usually smaller than JPEG and keeps transparency |
| Weak for | large photos, which come out several times bigger than a JPEG | government and exam forms, which often accept only JPG or PDF |
| Specification | Portable Network Graphics (PNG) Specification, Third Edition (W3C) | RFC 9649: WebP Image Format (IETF) |
When not to change PNG to WebP
- Do not send WebP to exam, visa or job-portal forms unless they list it: most accept only JPG, JPEG or PDF. Safari cannot write WebP from a canvas and PixelFit stops there with a message, so run this PNG to WebP step in Chrome, Edge or Firefox on a computer or Android phone; on iPhone and iPad every browser uses Safari's engine, so save JPG or PNG there.
- If the destination already accepts PNG, upload the original: every change of format re-encodes the pixels.
Browser support for PNG and WebP (October 2026)
Reading PNG (.png): Chrome, Edge, Firefox, Safari (every current browser). caniuse puts PNG support at about 97.49% of browsers in use (data updated 29 October 2026).
Writing WebP from that PNG: Chrome 50+, Edge 79+, Firefox 96+; Safari cannot encode it (its canvas hands back a PNG), and on iPhone and iPad every browser, Chrome and Firefox included, uses Safari's engine, so PixelFit stops there and suggests JPG instead of saving a PNG under a .webp name (MDN compatibility data for canvas.toBlob, checked 31 October 2026).
Where PNG files come from
PNG files are usually screenshots, exported graphics, scanned signatures or images with a transparent background. Photos saved as PNG are large because PNG keeps every pixel exactly.
WebP can store the same transparency and is often much smaller, which is why sites switch PNG artwork to WebP.
Sources
- Portable Network Graphics (PNG) Specification, Third Edition (W3C), W3C, checked 31 October 2026: w3.org/TR/png-3/
- RFC 9649: WebP Image Format (IETF), IETF, checked 31 October 2026: rfc-editor.org/rfc/rfc9649
- caniuse.com “PNG alpha transparency” support table, data of 29 October 2026 (CC BY 4.0): caniuse.com/png-alpha
- MDN browser-compat-data, HTMLCanvasElement.toBlob (which browsers write WebP), CC0, checked 31 October 2026: github.com/mdn/browser-compat-data/blob/main/api/HTMLCanv…
- Test photo “President Barack Obama.jpg” by Pete Souza (Official White House photo), public domain, measured by PixelFit with sharp 0.35.5 / libvips 8.18.7 on 31 October 2026: commons.wikimedia.org/wiki/File:President_Barack_Obama.jpg
Frequently asked questions
Can I convert PNG to WebP for free?
Yes. The PNG to WebP change runs free on your device, with no sign-up and no upload, one file or up to 25 at a time; Pro raises the batch to 500 with one ZIP download.
How do I convert PNG to WebP?
Drop the PNG on the tool above, keep WebP selected, and download the .webp file. Add a KB limit if the destination has one.
Does converting PNG to WebP reduce quality?
WebP is lossy: the exact pixels of the PNG are approximated, which is invisible on photos at high quality but can blur sharp text and edges. In our test a 1281×1600 px portrait went from 4.46 MB as PNG to 141 KB as WebP (−97%).
Why convert PNG to WebP?
WebP suits web pages, where it is usually smaller than JPEG and keeps transparency; PNG is a poor fit for large photos, which come out several times bigger than a JPEG.
Related
More PNG format changes
- WebP to PNG the reverse direction
- PNG to JPG same PNG input
- PNG to PDF same PNG input
Other files to WebP
- AVIF to WebP also ends as WebP
- SVG to WebP also ends as WebP
- JPG to WebP also ends as WebP