画像とデザインツール

Convert from JPG

「Convert from JPG」は画像とデザインに使えるブラウザツールです。入力内容と結果は通常この端末内で処理され、登録は必要ありません。

ブラウザ内で処理登録不要プライバシーの説明 ↗

LOCAL JPG CONVERSION

Turn a JPG into PNG or WebP

Decode one JPEG in your browser, choose an output format, and download a new file without uploading the image.

No file selected

One JPG only, up to 20 MB and 40 megapixels. The source stays in this browser.

Canvas creates a new file from decoded JPEG pixels. Original EXIF, ICC profile, comments, thumbnails, and compressed JPEG data are not copied. Dimensions and visible pixels are retained; PNG output is lossless after decode, while WebP quality can discard detail.

使い方

使い方

  1. Choose one JPG up to 20 MB and 40 megapixels.
  2. Select PNG for a lossless-after-decode output or WebP and set its quality.
  3. Preview the converted image and download it when it looks right.

PNG or WebP output

PNG preserves the decoded pixels without an additional quality setting, but it can be larger than the JPG. WebP uses the selected quality and may be smaller, with some visual detail discarded as quality decreases.

Dimensions and pixel boundaries

The output keeps the JPEG natural width and height. Inputs above 20 MB, above 10,000 pixels on either side, or above 40 megapixels are rejected so browser memory use stays bounded.

Metadata and privacy

Canvas conversion writes a fresh image from decoded pixels. EXIF orientation, GPS data, ICC profiles, comments, thumbnails, and original compression are not preserved. The selected image is processed in this browser and is not uploaded.

よくある質問

あわせて知りたいこと

Is PNG output exactly the original JPG?

No. PNG is lossless for the pixels decoded by the browser, but JPEG decoding has already applied the source JPEG compression. The PNG is a new file and does not preserve JPEG metadata or compressed bytes.

Which output should I choose?

Choose PNG when you want a lossless-after-decode copy. Choose WebP when a modern, usually smaller file is more useful and you can accept quality-based encoding.

Will the image dimensions change?

No. This converter retains the source width and height. Use an image resizer when you need different pixel dimensions.

Does this upload my JPG?

No. The file is read, decoded, and encoded locally by your browser.