Convertisseur de Formats

Convert images between formats in your browser - quality and upscale options included

100 % gratuit. Fonctionne entièrement dans votre navigateur : vos fichiers et données ne quittent jamais votre appareil et rien n'est envoyé à un serveur.

cloud_upload

Glissez-déposez les fichiers ici

ou parcourir pour importer

Supports PNG, JPG, WebP, and BMP - processed locally in your browser

Traité dans votre navigateur - votre fichier ne quitte jamais cet appareil.

Jump to the next useful tool without leaving your flow.

See more

À propos de cet outil

Choosing an image format is a decision between three things: file size, transparency support and compatibility. JPG is lossy and compresses photographs extremely well, but cannot store transparency and degrades slightly each time it is re-saved. PNG is lossless, supports transparency and keeps text and sharp edges crisp, at the cost of much larger files for photographic content. WebP is the modern option that does both - roughly 25-35% smaller than JPG at the same quality, with transparency support - and is now supported by every current browser, though older software and some print workflows still refuse it. The rule that follows from this is simple: photographs to JPG or WebP, graphics and anything with transparency to PNG or WebP, and PNG when maximum compatibility matters more than size. This converter also lets you control output quality for JPG and WebP, and optionally upscale images 2× with sharpening to make small photos sharper - though upscaling cannot recover detail that was already lost in a heavily compressed original. Everything runs in your browser: images are decoded on a canvas and re-encoded on your own device, so nothing is uploaded.

Comment utiliser cet outil

  1. Add your imageDrop the file in or browse to select it. Its current format and size are shown for reference.
  2. Choose the target formatPNG, JPG, WebP or BMP. Pick based on whether you need transparency, the smallest file, or the widest compatibility.
  3. Adjust quality optionsFor JPG and WebP, set the output quality slider. Optionally enable 2× upscale with sharpening to increase resolution.
  4. Convert and downloadThe image is re-encoded in your browser in the format you selected. Your original file is unchanged.

Pourquoi l’utiliser

  • Covers PNG, JPG, WebP and BMP in one tool.
  • Runs entirely in your browser - images never leave your device.
  • Quality slider for JPG and WebP so you control the size-vs-quality trade-off.
  • Optional 2× upscale with sharpening for small or low-resolution images.
  • No account and no watermark.

Usages courants

  • Meeting an upload requirement that accepts only specific formats.
  • Converting photographs to WebP to speed up a website.
  • Turning a WebP downloaded from the web into PNG or JPG for software that will not open it.
  • Converting a logo to PNG so it can sit on a coloured background with transparency intact.
  • Standardising a mixed folder of images into one format.

Conseils pour de meilleurs résultats

  • For the web, WebP is usually the right answer now - meaningfully smaller than JPG with transparency support, and universally supported by current browsers.
  • Convert from the highest-quality original you have. Every conversion through a lossy format costs a little more detail.
  • If the image has transparency, converting to JPG will fill it with a solid colour. Use PNG or WebP instead.
  • PNG remains the safest choice when a file has to open in old software or an unpredictable environment.
  • Converting alone will not hit a specific file size. Use the Image Compressor, or Resize Image to KB for an exact target.

Erreurs à éviter

  • Converting a JPG to PNG and expecting better quality. It preserves what remains; it cannot restore what was already discarded - and the file gets much larger.
  • Converting a logo or screenshot to JPG, where compression puts visible halos around text and sharp edges.
  • Losing transparency by converting to JPG without realising the background will become solid white.
  • Converting the same image repeatedly between lossy formats, which compounds the degradation each time.
  • Choosing PNG for photographs on a website, which can multiply the page weight for no visible gain.

Formats pris en charge

  • JPG
  • PNG
  • WebP
  • GIF
  • BMP

Options disponibles

  • Source format
  • Target format
  • Quality

Questions fréquentes

Add your image above, pick PNG, JPG, WebP or BMP as the target, adjust quality or upscale options if needed, and convert. Everything runs in your browser - only the encoding changes unless you enable 2× upscale.

Yes. No account, no watermark and no conversion limit.

JPG for photographs where size matters and transparency does not. PNG for logos, screenshots, text and anything needing transparency, or when maximum compatibility is essential. WebP when you want both - smaller than JPG and supports transparency, which makes it the best default for the web.

Yes. For JPG and WebP, use the quality slider to export at up to 100%. You can also enable 2× upscale with optional sharpening to increase resolution. Upscaling makes small images larger and sharper, but it cannot restore detail that was already discarded by heavy compression.

Converting to a lossy format like JPG introduces some loss. Converting to a lossless format like PNG loses nothing further - but it also cannot recover detail an earlier lossy save already removed.

It is lost. JPG has no alpha channel, so transparent areas are filled with a solid colour, usually white. Convert to PNG or WebP if the transparency matters.

Yes, for the web. Every current browser supports it, and it is typically 25-35% smaller than JPG at the same quality. The caveat is outside the browser - some older desktop software and print workflows still do not accept it, which is when converting back to PNG or JPG helps.

Not by default - width and height stay the same unless you enable 2× upscale. Use the Image Resizer if you need a specific size without upscaling.

No. The conversion uses your browser's own canvas and image encoder, so the file never leaves your device. You can disconnect from the internet after the page loads and it will still work.

Les gens recherchent aussi

  • image format converter free
  • convert webp to jpg
  • convert image to webp
  • change image format online
  • png jpg webp converter
  • best image format for website
  • bulk image format converter

Useful in

Related guides