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Format Converter

Convert between PNG, JPEG, WEBP instantly

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PNG, JPEG, WebP — when to use which

Choosing the wrong format is one of the most common causes of unnecessarily large web pages. Here's the decision table:
SituationRecommended FormatWhy
Photograph / complex sceneJPEG or WebPLossy compression works well on continuous tones
Logo / icon / UI screenshotPNG or WebPLossless — sharp edges and text stay crisp
Transparent image (e.g., sticker)PNG or WebPJPEG has no alpha channel
Web page asset (fast loading)WebP25–35% smaller than JPEG at equivalent quality
Print or archivalPNGLossless, no generation loss on re-save

How the conversion works

Format conversion runs entirely via the browser's native Canvas API: your image is decoded into a raw pixel buffer, then re-encoded by the browser's built-in codec:
    1. JPEG → browser uses its libjpeg-turbo implementation
    2. WebP → browser uses libwebp
    3. PNG → browser uses libpng
No third-party encoding library is loaded. The exact same codec your browser uses to display web images is used to convert them. This means encoding speed is fast, output quality matches what you'd get from a native application, and there's no extra binary to download.

Important format-specific notes

Converting to JPEG from a transparent PNG: JPEG has no alpha channel. The tool fills transparent areas with solid white before encoding. If you need the transparency preserved, choose WebP instead.

Converting to WebP: WebP supports both lossy and lossless modes. The tool exports lossy WebP by default (best file size for photos). Transparent PNGs are exported as lossless WebP to preserve the alpha channel.

Re-converting a JPEG: Each JPEG encode/decode cycle introduces a small amount of additional quantisation noise ("generation loss"). For archival purposes, always keep the original and only generate the converted version as a derivative.

How to use the Format Converter

  1. Upload — Drag and drop any PNG, JPEG, or WebP file.
  2. Choose format — Select your target from the dropdown.
  3. Convert and download — Completes in under 2 seconds.
💬 FAQ

FAQs about Format Converter

Everything you might be wondering — answered.

What happens to PNG transparency when I convert to JPEG?+
JPEG does not support an alpha channel. The Canvas fill colour (white by default) is composited behind the transparent pixels before JPEG encoding. The output has no transparency — transparent areas become solid white.
Does WebP support transparency?+
Yes. WebP supports both lossy and lossless modes with full alpha channel support. Converting a transparent PNG to WebP preserves the transparency and typically reduces file size by 25–30%.
Is there a quality loss when converting PNG to JPEG?+
JPEG encoding is lossy by definition. Even at high quality settings, some detail is discarded (mainly in high-frequency areas). PNG is lossless, so PNG→PNG is always zero loss. For photos, PNG→JPEG at q=90 is visually transparent to most viewers.
Does the tool use any third-party encoding library?+
No. The conversion uses the browser's native canvas.toDataURL() and canvas.toBlob() APIs, which delegate to the browser's own built-in codec implementations (libjpeg-turbo, libwebp, libpng depending on format).