Both are useful web formats. Your choice should account for the receiving platform, the actual output, and how long you are willing to spend encoding.
Check the complete workflow
Your visitors’ browsers are only one part of compatibility. Check your CMS, image editor, email workflow, and any marketplace receiving the file. Make a JPEG or PNG copy where a receiving tool requires it.
Measure instead of assuming
AVIF does not automatically produce the smallest file for every image. Quality values are also not visually equivalent between encoders. Use a representative photo, a transparent graphic, and a text-heavy asset from your own work to compare.
Account for encoding time
PikoZip performs processing on your device. AVIF can take more time, particularly on mobile hardware or larger images. If a fixed format is already appropriate, selecting it directly avoids the extra encodes in Smart mode.
Keep a fallback when it matters
Keep an original master and the output required by your destination. If you develop a website, serve the formats your application supports and test the finished page, rather than judging the export in isolation.
A measured comparison from PikoZip
Our published four-source comparison includes a product photo, screenshot, transparent mark and gradient, all at unchanged dimensions. At setting 85 the photo was 271,130 bytes in WebP and 339,356 bytes in AVIF, while the screenshot was 30,164 bytes in WebP and 8,875 bytes in AVIF. The same numeric quality setting is not equal visual quality across codecs. Download and inspect the outputs below; the measured winner changes with the source.
WebP and AVIF: compare the actual output
The same source pixels and dimensions were encoded at setting 85 in both codecs. That number is not equal visual quality across formats. Download the images and review text, gradients and edges. Timing is the median of three pipeline runs on a shared Linux Node runner; phones and browsers can differ substantially.
| Source | Format | Output bytes | Median pipeline time | Output |
|---|---|---|---|---|
| Product photo | WEBP | 271,130 | 500 ms | WEBP |
| Product photo | AVIF | 339,356 | 1,546 ms | AVIF |
| Interface screenshot | WEBP | 30,164 | 165 ms | WEBP |
| Interface screenshot | AVIF | 8,875 | 2,029 ms | AVIF |
| Transparent mark | WEBP | 9,776 | 133 ms | WEBP |
| Transparent mark | AVIF | 7,403 | 288 ms | AVIF |
| Smooth gradient | WEBP | 11,916 | 244 ms | WEBP |
| Smooth gradient | AVIF | 5,488 | 641 ms | AVIF |
How to interpret these results
We used actual PikoZip worker functions and pinned WebAssembly codecs in a Node harness, with UPNG-decoded RGBA and unchanged dimensions. The browser’s decode/color pipeline can differ. PNG Lossless outputs matched the reference decoded pixels. This is an engineering check, not proof of perceptual equivalence, and is not a TinyPNG comparison.
One original was already compact: all four PNG modes kept the 6,861-byte gradient source. The uncompressed screenshot has unusually large room for reduction, so its saving must not be presented as typical of all screenshots.
Download full measurements and SHA-256 source hashes · Download originals and results ZIP (11.2 MiB)
Reproduce with node scripts/publish-compression-evidence.mjs in the matching source checkout. The measurements were recorded on 11 November 2026; exact timings can vary between runs.
Explore the complete benchmark and PNG mode results
Further reading: Google’s image performance guide and the WebP format documentation.
Put the guide into practice.
Start with one representative image, inspect the result, then prepare the rest of the batch.
Open the compressor