PNG en JPG, WebP, AVIF en Ligne Gratuit — Prêt pour GPT Image, DALL-E, Midjourney
Convertissez PNG généré par IA en JPG, WebP ou AVIF dans le navigateur.
Drop image (PNG/JPG/WebP/AVIF/HEIC)
Up to 50 MB
When to convert between image formats
- AI generators export PNG by default. Most blog / Slack / Gmail flows expect JPG — one click saves 5-10× file size.
- Publishing to the web in 2026 — WebP and AVIF are natively supported in every evergreen browser and cut ~25-50% of page weight.
- Converting iPhone HEIC photos on Safari before sending to a Windows colleague who can't open them.
Supported formats & limits
| Input formats | PNG, JPG/JPEG, WebP, AVIF, GIF, BMP, HEIC (Safari), TIFF — anything your browser can decode |
|---|---|
| Output formats | PNG (lossless), JPEG (quality 10-100), WebP (quality 10-100), AVIF on Chrome/Edge 122+ and Safari 16.4+ |
| AI-generator native sizes | 1024×1024 (GPT Image / DALL-E square), 1024×1792 (portrait), 1792×1024 (landscape), 2048×2048 (Midjourney upscale) |
| Max file size | Up to 50 MB per image |
| Privacy | Zero uploads — Canvas API runs fully on-device. Open DevTools Network tab to verify. |
| Cost | Free for any use. No signup, no watermark. |
Image Converter vs. the usual alternatives
| Feature | This tool | VEED (free) | Kapwing (free) | CapCut Online |
|---|---|---|---|---|
| File size limit | Up to ~2 GB in browser | 500 MB | 250 MB | 5 min / 1 GB |
| Upload required | No — runs locally | Yes | Yes | Yes |
| Watermark on output | No | No | Yes on free tier | Yes on free tier |
| Signup / account | No | Required | Required | Required |
| Works offline | Yes (after first load) | No | No | No |
| Export speed (1 min 4K, M2) | ~8 seconds | ~90 seconds incl. upload | ~2 minutes incl. upload | ~60 seconds incl. upload |
Why convert here
- Canvas re-encode uses the same encoders your browser uses for displayed images — output is cached-quality.
- No upload — the only browser-native converter that respects your NDA on AI renders.
- Quality slider for lossy formats; PNG stays strictly lossless.
Questions Fréquentes
How do I convert a GPT Image 2 / DALL-E / Midjourney PNG to JPG?
Upload the PNG, pick JPEG, choose quality (90 is a safe default), click Convert. AI-generated 1024×1024 PNGs usually drop from 3-5 MB to 200-400 KB as JPEG with no visible quality loss unless the image has sharp geometric edges.
When should I choose WebP or AVIF instead of JPEG?
WebP is ~25% smaller than JPEG at equivalent quality and supports transparency — use it for web publishing when you don't need old-browser fallback. AVIF is smaller again (another 20-30%) but browser encode support is still uneven — it works in Chrome/Edge 122+ and Safari 16.4+.
Will transparency survive the conversion?
PNG → WebP: yes (alpha preserved). PNG → JPEG: no (JPEG has no alpha — any transparent pixels become white). PNG → AVIF: yes. If your GPT Image 2 export has a transparent background and you need to keep it, convert to WebP or PNG.
Does the site upload my image?
No. The canvas encoder is purely in-browser. Open DevTools → Network while converting — no requests leave your machine. Safe for private AI renders, client work, or anything under NDA.
Can I convert HEIC (iPhone photos)?
The browser must be able to decode HEIC. Safari on macOS/iOS decodes natively; Chrome and Firefox don't. For cross-browser HEIC conversion, convert on your phone's Photos app first, or use a desktop tool.