Priconvert

JPG to AVIF converter with local WASM encoding

Single mode is free — upload a JPG, preview the AVIF, adjust quality, and download. Pro users can batch convert to a ZIP. The AVIF encoder loads once per browser session when you need it.

Convert JPG to AVIF

Loading usage…Local
Preparing the AVIF encoder (one-time load for this session)…

Drop an image here

Supported: JPG, JPEG.

Supported: JPG, JPEG

Processed locally — nothing uploaded.

This page is a focused entry point into the same privacy-first converter on Priconvert — processed locally in your browser, with no uploads for conversion. Pro users can batch convert, resize, compress, and download ZIP files from the converter.

Open the full converter on the homepage · View all formats

About this converter

What does this JPG to AVIF converter do?

Create smaller, modern AVIF files from JPG photos without uploading them. Priconvert encodes AVIF with a local WASM codec (not unreliable canvas.toBlob), lets you adjust quality and resize, and keeps processing on your device.

JPG to AVIF conversion re-encodes a JPEG photo into the AV1-based AVIF format, which often produces a smaller file at a comparable visual quality for the web. Priconvert does not rely on canvas.toBlob("image/avif") alone — that API silently falls back to PNG in many browsers. Instead, encoding uses @jsquash/avif WASM loaded on demand and cached for the session.

Use this when you want modern delivery sizes for sites that already serve AVIF (with JPG fallbacks), or when you simply want a more efficient archive copy. JPG has no transparency, so the AVIF output is opaque as well.

Compression, quality, and browser notes

Input: .jpg / .jpeg. Output: .avif with adjustable quality. Resize and Pro batch/ZIP use the same shared conversion pipeline as other Priconvert tools.

AVIF advantages: typically better compression efficiency than JPG or WEBP at similar quality, and wide decode support in current browsers. Disadvantages: encoding is CPU-heavier than JPG; the first conversion in a session may wait while the WASM encoder loads; older apps may not open AVIF.

If the AVIF encoder cannot initialize (network blocked, unsupported environment), Priconvert disables AVIF output with a clear message instead of producing a mislabeled PNG.

Format guide

When should I use JPG?

JPG remains the most universally compatible format for photographs and continuous-tone images. Use it when a form, CMS, printer, or older device still expects JPEG, or when you need the smallest friction for sharing with non-technical recipients.

Do not use JPG for graphics that need transparency or for content with hard edges and flat colors — those compress poorly and show ringing. For modern websites, WEBP or AVIF often give better size/quality tradeoffs when compatibility allows.

What is AVIF?

AVIF is an image format based on the AV1 video codec. It typically achieves higher compression efficiency than JPG and often WEBP for the same visual quality, which makes it attractive for bandwidth-sensitive sites and large photo libraries.

Browser support is now broad on current desktop and mobile engines, but encoding is more expensive than JPG. Priconvert encodes AVIF locally with a WASM encoder on first use (cached for the session). Animated AVIF is not supported in this tool.

WEBP vs AVIF

Both are modern alternatives to JPG/PNG. AVIF usually wins on compression ratio for photographic content; WEBP is faster to encode/decode in many environments and has slightly longer production maturity. WEBP also has a straightforward lossless mode that is a practical PNG replacement for many UI assets.

Prefer AVIF when minimizing bytes matters most and encode time is acceptable. Prefer WEBP when you want a balanced default with broad tooling support. Keep JPG as a compatibility escape hatch when a consumer cannot accept either format.

How it works

How JPG to AVIF conversion works

Decode JPG with native browser APIs, then encode AVIF with a session-cached WASM module.

  1. 1

    Choose a JPG

    Drop a .jpg or .jpeg file. It stays on your device for local conversion.

  2. 2

    Encoder loads once

    On first AVIF export in the session, Priconvert loads the WASM encoder and caches it so later files are faster.

  3. 3

    Tune quality and size

    Use the quality slider and optional resize, then preview the result before downloading.

  4. 4

    Download AVIF

    Save the .avif file locally. Batch mode on Pro packs multiple outputs into a ZIP.

Privacy

Local encoding — your JPG is not uploaded

Encoding happens in your browser. The WASM module is public codec code, not your photo.

  • Your image pixels are processed on-device.
  • The one-time encoder download is the codec itself, not your JPG.
  • Priconvert does not upload your file for JPG → AVIF conversion.

FAQ

JPG to AVIF questions

Encoding, quality, and compatibility questions for JPG → AVIF.