What this tool does
Image Converter decodes one supported still image and re-encodes it to WebP, JPEG, PNG, or AVIF. Default output is WebP at quality 85. PNG input is suggested toward WebP; WebP input is suggested toward JPEG.
When to choose it instead of a similar DevToolKit tool
- Choose PNG to WebP for a PNG-only workflow with quality 40–100 and proportional max-dimension downscale.
- Choose WebP to PNG when you only need a PNG compatibility copy and no quality slider.
- Choose Image Compressor when you want compression presets and a -compressed filename.
- HEIC is not accepted here; use HEIC to JPG.
Supported inputs, limits, and output behavior
- Input
- One JPG, PNG, WebP, or AVIF, 20 MB.
- Output
- {base}.webp|.jpg|.png|.avif
- Quality
- Shown for JPEG, WebP, and AVIF (slider 20–95). PNG encoding omits the quality argument.
- JPEG matte
- backgroundColor fill before drawImage.
How the transformation actually works
convertImageInBrowser loads the object URL, resolveOutputDimensions, clears or fills the canvas, draws with high smoothing, then canvas.toBlob. AVIF is checked with toDataURL before encode.
Step-by-step workflow
- Click Choose image or drop one supported file.
- Pick an output format.
- Set Quality and JPEG background if those controls show.
- Optionally turn on Resize while converting and type Width and/or Height.
- Click Convert image.
- Compare Original size and Converted size on the download.
What can change in the output
Lossy formats quantize. PNG stores the canvas pixels without a quality argument; that is not a byte-identical copy of a PNG source. Animation, EXIF, and ICC are not copied by this encoder. Resize can change aspect ratio if both width and height are set.
Known limitations and failure cases
- AVIF export can fail in browsers without canvas AVIF.
- There is no do-not-enlarge switch (unlike Image Resizer).
- Animated sources become a still frame from the Image decoder.
Privacy / where data goes
Conversion runs in the browser. The file is not uploaded to a conversion API. Identified analytics may include byte counts, formats, quality, and dimensions, not the image pixels.
Practical output-review checklist
- Check edges if you flattened transparency to JPEG.
- Confirm AVIF opens in the destination app.
- Compare file size; conversion is not a size-reduction promise.
- If you set both width and height, confirm the aspect ratio is still acceptable.