When to use WebP instead of PNG
PNG and WebP both store pictures, and they are not interchangeable. PNG is the older, widely supported choice for graphics that must stay sharp. WebP is the smaller choice for photographs and for many interface images once you have checked the result. Picking the format before you export saves a second conversion later.
WebP and PNG compared
| WebP | PNG | |
|---|---|---|
| Compression | Lossy or lossless | Lossless |
| Typical size | Smaller. Google reports lossless WebP is 26% smaller than PNG | Larger |
| Transparency | Yes | Yes |
| Best for | Photos and images on public web pages | Graphics with text, files you will edit again |
| Old software | Sometimes rejected | Opens almost everywhere |
What each format keeps
PNG is lossless by default. A logo, a screenshot of text, a diagram with flat color, and a UI icon usually look the same after you save them as PNG. PNG also stores transparency as a clean mask, which matters when a graphic sits on a colored background or in a layout that changes.
WebP can be lossless or lossy. The lossy mode is what makes a photo much smaller than the same photo saved as PNG. Edges of text and hard lines can pick up a little blur or ringing if the quality is pushed toward the smallest file. A photograph of a room usually hides that. A screenshot of a spreadsheet often does not.
Both formats can carry an alpha channel. If the picture has no transparency, you do not gain anything by keeping a format that is larger only because it could have stored transparency.
A practical rule
Use PNG when someone will edit the file again, when the image is a graphic with text, or when the destination is old software that still rejects WebP. Use WebP when the picture is a photo or a busy illustration, the page is on the public web, and you have looked at the download at the size it will actually be shown.
If you already have a PNG and you want the smaller file, PNG to WebP does that conversion. If a site or an email client will not open the WebP, WebP to PNG brings it back to the format those tools expect. A camera JPEG is a different starting point: JPG to PNG does not make a JPEG sharper, and WebP to JPG is the path when the destination wants a JPEG.
The quality control on the tool page is Smallest, Balanced, or High. Balanced is the default. Smallest is for a picture that is already busy and only needs to be recognizable. High is for a photo you will crop or print. The preset is stored with the job, so history can run the same choice again while the upload is still on the server.
What conversion does not fix
Turning a tiny, already compressed image into WebP will not recover detail that was thrown away. Turning a WebP into PNG makes a larger file and does not remove compression that already happened. If the PNG was exported at the wrong pixel size, change the size in the source program first. MyConvert does not redraw the artwork.
Animated WebP and animated PNG are a separate case. A short animation may survive, but a long one is better left in the format the player already uses. Do not send a file you are not allowed to upload. Guest results stay available for 30 minutes after the job finishes. Signed-in results stay for 24 hours.
More image comparisons are on the image hub. If the file is a phone photo in HEIC rather than PNG, start with the HEIC to JPG guide instead of this one.