Image Format Converter

Convert image formats in your browser

JPEG, PNG, and WebP store pixels differently. This image converter changes the file encoding while preserving the source image's natural width and height. Select an image, choose an output format, adjust quality for lossy formats, then download the converted file.

All processing uses the browser Canvas API. The source image stays on your device instead of being uploaded to a conversion service.

JPEG, PNG, and WebP compared

Format	Compression	Transparency	Best for
JPEG	Lossy	No	Photos and broad compatibility
PNG	Lossless	Yes	Logos, screenshots, and diagrams
WebP	Lossy or lossless	Yes	Smaller web images

JPEG

JPEG works well for photographs with gradients and natural detail. Higher quality retains more detail but usually creates a larger file. Because JPEG has no alpha channel, transparent pixels need a solid background during conversion.

PNG

PNG preserves sharp edges and transparency. Canvas PNG export ignores the quality slider because PNG encoding is lossless. It is usually a better choice for interface screenshots, icons, and line art than JPEG.

WebP

WebP often produces smaller files than JPEG or PNG at a similar visual quality. It supports transparency and is widely supported by current browsers. Check target-browser requirements before using it for older applications.

How browser conversion works

1. Browser decodes the selected image.
2. Canvas receives the original pixel dimensions.
3. Canvas exports a new Blob in the selected MIME type.
4. The Blob becomes a local download URL.

Conversion does not change width or height. Re-encoding an already compressed JPEG can introduce additional loss, so keep an original source file for repeated edits.

const canvas = document.createElement("canvas");
canvas.width = image.naturalWidth;
canvas.height = image.naturalHeight;
canvas.getContext("2d").drawImage(image, 0, 0);
canvas.toBlob((blob) => {
  // Save or preview the converted Blob.
}, "image/webp", 0.9);

from PIL import Image

image = Image.open("source.png")
image.save("converted.webp", "WEBP", quality=90)

magick source.png -quality 90 converted.jpg

Common conversion choices

PNG to JPEG

Use for photographs or when a target system does not accept PNG. Transparent areas cannot remain transparent in JPEG and may become a solid background.

JPEG to WebP

Use to reduce web delivery size. Keep quality high enough to avoid visible blocking around text and edges.

WebP to PNG

Use when a workflow requires lossless output or broad editing-tool compatibility. PNG may be larger even though it preserves every pixel.

Privacy and file limits

The tool performs conversion locally. No account or upload is required, and the original file is not modified. Very large images can be limited by browser memory; reducing the source dimensions first may help when a conversion fails.

Animated GIF files are generally decoded as one frame by canvas, so converting an animated GIF produces a static output image. Browser support also determines which source formats can be decoded.