WebP to AVIF converter

WebP → AVIF converted our 320 byte transparent WebP into a 1,088 byte AVIF, so small alpha art did not shrink.

Converted with Image engine · input deleted within 24 h
Free: 5 conversions a day · 5 MB each
Higher limits →

From real runs

What you get — and what changes

Element	Result	What happens
Decoded pixels	Kept	The conversion starts from the WebP decoder output, so visible content transfers into the AVIF image.
Alpha channel	Kept	The transparent WebP source converted successfully to AVIF without requiring a background color.
Prior WebP loss	Kept	If the WebP was lossy, AVIF receives those already-compressed pixels and cannot reconstruct the original.
Small asset size	Changed	Our tiny transparent WebP expanded from 320 bytes to 1,088 bytes in the AVIF output.
Animation	Lost	The image engine reader flattens animated inputs to the first frame before writing single-image AVIF.
Metadata	Changed	WebP container fields are not preserved as a matching metadata set in the AVIF derivative.

Decoded pixels Kept
The conversion starts from the WebP decoder output, so visible content transfers into the AVIF image.
Alpha channel Kept
The transparent WebP source converted successfully to AVIF without requiring a background color.
Prior WebP loss Kept
If the WebP was lossy, AVIF receives those already-compressed pixels and cannot reconstruct the original.
Small asset size Changed
Our tiny transparent WebP expanded from 320 bytes to 1,088 bytes in the AVIF output.
Animation Lost
The image engine reader flattens animated inputs to the first frame before writing single-image AVIF.
Metadata Changed
WebP container fields are not preserved as a matching metadata set in the AVIF derivative.

Sample conversions

Transparent WebP icon

Input: A 96×64 lossless WebP with alpha around overlapping logo shapes, 320 bytes on disk.
Output: A 1,088 byte AVIF. It remained an image with transparency support, but the tiny source did not benefit from AVIF size savings.

Lossy WebP hero candidate

Input: A WebP hero image already compressed by a CMS, with faint banding in a gradient background.
Output: An AVIF derivative for newer browsers. The banding was still part of the image because it came from the source WebP.

A real WebP → AVIF run

We converted our WebP sample (23 KB) with Image engine on 2026-10-20. It took 188 ms and produced a 21 KB AVIF file, about the same size as the input. The engine raised 1 warning, listed below.

Input · sample.webp · 23 KB

1200 × 800 px, extended VP8X

Width: 1,200
Height: 800
Encoding: extended VP8X

Output · sample.avif · 21 KB

1200 × 800 px, avif

Width: 1,200
Height: 800
Encoding: avif

Image metadata stripped from output.

Is your file a scan?

WebP → AVIF is the wrong first step for screenshots that need extraction. Run OCR or table extraction on the image content instead of only changing the codec.

Options and when to change them

quality: Lower it for large photographic WebP files when AVIF support is known; raise it when re-encoding creates visible artifacts.
width: Set width to produce one AVIF breakpoint rather than carrying the source WebP dimensions forward.
height: Use with width for exact cards, thumbnails, or ad image dimensions.
fit: Select contain for padding, cover for crop-to-fill, or fill only when distorted output is acceptable.

Do it yourself

ImageMagick 7

bash

magick in.webp -quality 80 out.avif

Your build must include both WebP and AVIF codecs, and animated WebP handling may differ.

WebP to AVIF by API or MCP

The HTTP API and the MCP server run the exact engine this page uses (Image engine); the response carries the same warnings the web converter shows. Check support first with GET /api/v1/pairs?from=webp&to=avif.

curl

curl -X POST https://filetypeconverters.com/api/v1/convert \
  -H "Authorization: Bearer $FTC_API_KEY" \
  -F "file=@input.webp" -F "from=webp" -F "to=avif" \
  -F 'options={"dpi":96}' \
  --output output.avif

Options this engine accepts for WebP → AVIF

Key	Applies to	Type	Default
dpi	Reading WebP	number	96

API reference

When this is the wrong conversion

Keep WebP when the target audience or app support for AVIF is uncertain.
Use WebP → PNG if transparent artwork needs editing rather than another delivery codec.
Go back to the original source asset if the WebP already contains compression artifacts you dislike.

WebP to AVIF questions

Does WebP → AVIF keep transparent areas?

It did for the tested transparent WebP. No background color was needed for the AVIF output.

Will WebP → AVIF always be smaller?

No. Our tiny alpha WebP grew from 320 bytes to 1,088 bytes, so check actual output before replacing assets.

What happens to animated WebP files?

The image reader flattens animated inputs to the first frame for this still-image path. Use animation or video tooling if motion matters.