Calculator
What the PNG to WebP does
PNG to WebP: converts your image to WEBP in the browser. Everything runs in your browser and the file is never uploaded.
The PNG to WebP works on a file you choose, without sending it anywhere. Everything runs on your own device, which means no waiting and no copy left on a server.
Typical users are people preparing images for the web. A smaller file that still looks right is usually only a few settings away.
Everything happens inside this page. Nothing you type is sent to a server, and there is nothing for us to store.
The meaning of each field, the formula in use, and a worked example that starts from the default inputs are all further down.
What do the PNG to WebP fields mean?
The PNG to WebP uses 2 inputs. You can work from the defaults, or clear them and start fresh, both work.
| Field | What to enter | Default |
|---|---|---|
| Image file | stays on your device | none |
| Quality % | accepts 10 to 100 | 90 |
How does the PNG to WebP work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same conversion.
Values are checked first: an out-of-range or non-numeric entry names the offending field instead of returning nonsense.
What a typical run looks like
You provide: Image file and Quality %
What happens: the file is read into memory by your browser, processed locally, and offered back as a download. It is never uploaded.
You get back: a processed file plus a short status summary in the tool panel.
The tab does the processing, so speed tracks your hardware and very large files fail on memory rather than on a quota.
PNG to WebP
WebP does everything PNG does (lossless compression and full alpha transparency) in a smaller file. For web delivery this conversion is close to free.
| Transparency | Preserved | full 8-bit alpha |
|---|---|---|
| Lossless mode | Available | typically 25 to 35% smaller than PNG |
| Lossy mode | Also available | much smaller again |
| Support | All current browsers | a fallback is rarely needed now |
Worth knowing
- Use lossless WebP for screenshots, logos and diagrams. Lossy WebP damages hard edges the same way JPEG does.
- Lossy WebP applies 4:2:0 chroma subsampling unconditionally, so saturated red or orange text degrades noticeably.
- The saving is largest on images with transparency, where PNG is at its least efficient.
- Keep the PNG original if the image is a source asset you will edit again.
Read next: JPEG, PNG, WebP or AVIF: Choosing an Image Format
How to use it
- Choose your file under Image file, or drag it onto the drop area.
- Set Quality % (10 to 100).
- Press Convert.
- You get Status back.
- Copy Link is the quickest way to send the exact scenario to someone else.
What this tool does not do
- EXIF metadata may be dropped during processing, which is usually desirable but is worth knowing.
- Re-encoding a lossy format such as JPEG always loses some detail, even at maximum quality.
- The result reflects the moment you ran it; anything that changes over time is not tracked.
- It validates ranges, not intent. A value can be accepted and still be the wrong one to use.
- Performance scales with your own hardware, since no server does the work.
Frequently asked questions
You need Image file and Quality %. Nothing starts empty, letting you treat it as a what-if tool rather than a data-entry form.
Quality % accepts 10 to 100. Out-of-range entries are refused up front, which is safer than silently clamping them.
It is not uploaded. Everything happens on your device, so no copy of your file exists on any server.
Nothing at all. There is no registration, no paywall and no per-use quota.
The conversion is exact for the method described above. Where a value is rounded for display, the underlying figure keeps full precision.