HEIC を AVIF に変換 — 次世代圧縮
プレミアム品質で可能な限り小さなファイルを得るために HEIC を AVIF に変換。100% ブラウザ内。
Output format
Quality
92%Drop your HEIC files — convert to AVIF
or click to browse · processed locally in your browser
Free · 5 of 5 watermark-free conversions left today
AVIF は最新の画像形式で、WebP よりさらに優れた圧縮を提供します。HEIC 写真を AVIF に変換して、高い視覚品質で最小のファイルサイズを実現 — モダンな Web サイトに最適。
How to convert HEIC to AVIF in 3 steps
Fast, free, and 100% private — every conversion happens inside your browser.
- 1
Drop your HEIC files
Drag one or more .heic photos into the converter, or tap to browse from your device. Folders and batches work too.
- 2
Choose AVIF as the output
AVIF is selected automatically on this page. Adjust the quality slider if you want a different balance between size and fidelity.
- 3
Download your AVIF files
Conversion runs locally — nothing is uploaded. Download files individually or grab a single ZIP for the whole batch.
What is the HEIC format?
HEIC (High Efficiency Image Container) is Apple's default photo format on iPhone and iPad since iOS 11. It uses HEVC compression to store images at about half the size of JPG with the same visual quality. The trade-off: outside of Apple devices, HEIC is still poorly supported — most Windows apps, Android phones, web platforms and email clients can't open it natively.
Why convert HEIC?
Converting HEIC to a widely-supported format like AVIF solves three problems at once: your photos open everywhere, they're easy to share with non-Apple users, and you can upload them to any website, CMS or printing service without errors. With this tool, conversion is instant, free and never sends your photos to a server.
HEIC vs AVIF — quick comparison
| HEIC | AVIF | |
|---|---|---|
| File size | Very small | Smallest — 30–50% smaller than JPG |
| Quality | Excellent | Excellent, often better than WebP at the same size |
| Browser support | Safari only | Chrome, Firefox, Safari, Edge |
| Best for | Apple devices | Modern websites, image-heavy apps |
Device & app compatibility
Where HEIC works out of the box, and where you really need AVIF.
| Platform | HEIC | AVIF |
|---|---|---|
| iPhone / iPad (iOS 11+) | Native | Native |
| macOS (10.13+) | Native | Native |
| Windows 10 / 11 | Extension required | Native |
| Android | Limited (recent versions only) | Native |
| Chrome, Firefox, Edge | Not supported | Supported |
| Gmail, Outlook, WhatsApp | Often rejected | Always accepted |
Need a different format?
Convert your HEIC photos to any other format — same tool, same privacy.
FAQ
AVIF は主要ブラウザでサポートされていますか？
はい — Chrome、Firefox、Safari、Edge すべてが AVIF をサポートします。
AVIF ファイルは JPG と比べてどれくらい小さいですか？
同等品質で通常 30〜50% 小さくなります。
変換はサーバーで行われますか？
いいえ。すべてブラウザ内で動作します。
多くの写真を一度に変換できますか？
はい、ZIP バッチダウンロードで可能です。
AVIF は可逆ですか？
AVIF は非可逆または可逆になり得ます。調整可能な品質で非可逆圧縮を使用しています。