Convert PNG to WebP (Portable Network Graphics to WebP)
Convert PNG to WebP online. Drop a Portable Network Graphics and get a WebP back at roughly 6% of the original byte cost. No sign-up, nothing saved.
- No account required
- Nothing saved
- Pixel-for-pixel, no resizing
ドラッグで比較、ビフォー / アフター
概要
Convert PNG to WebP. This tool re-encodes one Portable Network Graphics into a WebP of the same pixels at roughly 6% of the byte cost, without resizing, cropping, or colour-regrading. The net effect is faster pages, better Core Web Vitals scores, and lower CDN egress bills, because the same visual output travels in a much smaller container. Nothing is saved on our side.
WebP (WebP) is the modern web target. It was standardised in 2010 and reaches roughly 97%% of global browsers in 2026. At equivalent visual quality it cuts byte cost against PNG to about 6% on typical photographic content, which is why hero images on news sites, product galleries, and blog covers increasingly ship as WebP first with a legacy fallback.
PNG (Portable Network Graphics) is the incumbent your source probably came from: camera exports, older CMS uploads, and designer PSDs still save as PNG by default. It is supported everywhere, decodes fast, and is trivial to produce. The cost is size. Nothing in the PNG spec was designed for 2026 bandwidth budgets, and on photographic content a typical PNG file is measurably larger than the same pixels in WebP.
The trade-off is encoding speed and fallback plumbing. WebP takes more CPU to encode than PNG, which is why we run the encoder on our side instead of in your browser. Visual quality at the default target matches PNG on typical photographic content; screenshots and flat-colour illustrations retain their sharp edges. Shipping WebP in production usually pairs with a standard picture element and a PNG fallback for the last few percent of visitors.
When NOT to convert PNG to WebP: archival masters where every original pixel matters (keep the PNG), email-newsletter assets where a desktop client may still refuse WebP (ship JPEG there), and tiny icon-sized assets under 50x50 pixels where the WebP container overhead can exceed the encoded payload. For real hero art, product photography, and blog covers, WebP is the right 2026 default.
Every upload is held only while we re-encode it. The resulting WebP comes back on a one-time download link and is deleted the moment you fetch it, or sooner if you never come back. No account ties the upload to you, and the Privacy page lists every byte that touches disk. Converting PNG to WebP on BouseMutton leaves no residue behind.
WebP at a glance, against PNG
決める前に知っておきたい数字とトレードオフ。
WebP vs PNG byte cost
On typical photographic content, WebP reaches PNG-equivalent visual quality at roughly 6% of the bytes. Flat illustrations compress even better.
WebP browser support
WebP covers roughly 97%% of global browser traffic in 2026. Pair with a PNG fallback in a picture element for the remaining tail.
Codec era
WebP was standardised in 2010; PNG dates from earlier. The generation gap is why WebP fits the same image in much less space.
Encoding cost
WebP encoding is more CPU-heavy than PNG, which is why we run it on our side. Decoding in the browser is fast and not perceptibly slower than PNG.
No resizing
Conversion is pixel-for-pixel. A PNG that was 2048 pixels wide comes back as a WebP that is 2048 pixels wide. No silent dimension change.
Transparency preserved
WebP supports an alpha channel, so PNG files with transparent regions convert without losing transparency. Edges stay clean.
When to keep PNG
Keep the PNG for archival masters, for email-only delivery, and for icons under 50x50 pixels where the WebP container overhead outweighs its codec win.
使い方
3 ステップ、通常 5 秒以内に完了。
- 1
Upload a PNG
Drop a PNG up to 25 MB, or paste from the clipboard. No sign-up, no credit card, no account link.
- 2
We re-encode it as WebP
We run the WebP encoder on our side at a default quality that matches PNG visual quality for typical photographic content. Your battery stays cool.
- 3
Download your WebP
Your WebP comes back on a one-time download link. Fetch it and the file is deleted. Never come back and the file is deleted anyway.
実際の動作を見る
各スライダーをドラッグして、ビフォーとアフターをピクセル単位で比べてみてください。
画像は使い終わったら消えます
Every upload is held only while we re-encode it. The resulting WebP comes back on a one-time download link and is deleted the moment you fetch it, or sooner if you never come back. No account ties the upload to you, and the Privacy page lists every byte that touches disk. Converting PNG to WebP on BouseMutton leaves no residue behind.
- 数秒で処理
- データ保存なし
- アカウント紐付けなし
画像をアップロード
ワンクリック。サインアップ不要。あとはこちらにお任せ。
画像形式を変換
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無料の Convert PNG to WebP (Portable Network Graphics to WebP) は 1 枚ずつ処理します。クレジットパックなら 1 バッチで最大 50 枚、単一の ZIP ダウンロード、3 種類のプリセット (Blog / Social / Ecom) が使えます。 100 クレジット €5 から。一度払えば失効しません。
Glossary for PNG and WebP
上記の専門用語のやさしい説明。
よくある質問
新しいツールを試す前にもっとも多く寄せられる質問への回答。
関連ツール
この画像でおそらく必要になる他の作業へ、ワンクリックでジャンプ。
Compress image
Shrink an already-converted image further without changing its format, for bandwidth-constrained pages.
Strip EXIF metadata
Remove camera, GPS, and device metadata before publishing the converted image publicly.
Pad to a target aspect ratio
Extend the canvas to a 1:1 or 9:16 frame without losing pixels, before or after the format conversion.
Related reading on PNG, WebP, and image optimisation
このツールと相性のよい他のツール。
- Browse all format convertersSee the full set of PNG and WebP tools on BouseMutton, including compression, EXIF stripping, and resize.
- Portable Network Graphics -> JPEGAlso converting Portable Network Graphics to JPEG? This tool handles the same source in a different target format, for cases where the codec choice differs.
- JPEG -> WebPRun JPEG through this tool before or after conversion to WebP, depending on the workflow step you are at.
- Compress imageShrink an already-converted image further without changing its format, for bandwidth-constrained pages.