AVI → MP4
Convert legacy AVI to modern MP4 — 100% in your browser
Drop AVI files here
or click to browse — .avi, .divx, .xvid
AVI to MP4 Converter
Convert your old AVI videos to modern, universally compatible MP4 files — instantly, privately, and for free. No uploads, no signup, no watermarks. Batch convert as many videos as you want.
Everything you need to convert AVI to MP4
Powerful features designed for fast, private, and high-quality AVI to MP4 conversion.
Batch Conversion
Convert dozens or hundreds of AVI files to MP4 in one session. No file limits, no queue, no waiting.
100% Private
All processing happens in your browser. Your videos never get uploaded to any server — zero data leaves your device.
Quality Control
Choose your output quality level. Balance file size and video quality to suit your needs — from web-optimized to archival.
Codec Selection
Select between H.264 and H.265 (HEVC) codecs. H.265 offers up to 50% smaller files at the same quality.
No Signup Required
No account, no email, no registration. Just open the page and start converting — instantly and anonymously.
Unlimited & Free
Convert as many files as you want, as often as you want. No daily limits, no premium tiers, no watermarks — ever.
Why convert AVI to MP4?
AVI is outdated and bulky. MP4 is modern, efficient, and works everywhere — on every device, platform, and app.
Universal Compatibility
MP4 is supported by virtually every device, operating system, browser, and media player. No compatibility issues, ever.
Smaller File Sizes
MP4 with H.264/H.265 compression produces files 50–70% smaller than AVI while maintaining the same visual quality.
Web Platform Ready
Upload MP4 files to YouTube, social media, or embed in websites without format errors or transcoding delays.
Mobile Friendly
MP4 plays natively on iOS and Android devices. No third-party players or codec packs needed.
Streaming Optimized
MP4 supports progressive download and adaptive streaming. Start playing before the full file downloads.
Modern Codec Support
MP4 supports H.264, H.265, AAC, and other modern codecs. AVI is stuck with older, less efficient codecs.
When to use an AVI to MP4 converter
Old Video Archive
Convert old AVI home movies and archived footage to MP4 for modern playback on any device.
Web & Social Media
Upload videos to YouTube, Facebook, Instagram, or your website — most platforms require or prefer MP4.
Mobile Playback
Convert AVI files to MP4 so they play natively on iPhones, Android phones, and tablets without extra apps.
Video Editing
Import MP4 files into modern video editing software like Premiere Pro, DaVinci Resolve, or Final Cut Pro.
Email & Sharing
MP4 files are smaller and more shareable. Send videos via email or messaging apps without size issues.
Cloud Storage
Save storage space by converting bulky AVI files to compact MP4 before uploading to cloud services.
Convert AVI to MP4 in 3 simple steps
No technical knowledge needed. Just upload, convert, and download.
Upload AVI Files
Drag and drop your AVI videos or click to browse. Select one file or many — batch conversion is fully supported.
Convert Instantly
Your AVI files are converted to MP4 right in your browser. No upload, no waiting queue — processing is instant.
Download MP4
Download your converted MP4 files individually or all at once. No watermarks, no signup, no limits.
Tips for the best AVI to MP4 results
Choose the Right Codec
For web and mobile, H.264 is the safest choice — universally supported. For maximum compression, use H.265 (HEVC) if your target platform supports it.
Balance Bitrate & Quality
For web use, 2–4 Mbps is a good range for 1080p. For archival, use 8+ Mbps. Higher bitrate means better quality but larger files.
Batch Convert for Efficiency
Convert all your old AVI files at once. Select multiple files, set your quality once, and let the tool process them all.
Check Audio Sync
After conversion, verify audio synchronization. AVI files sometimes have variable frame rates that can cause audio drift in MP4.
Keep Originals Safe
Always keep your original AVI files as a backup until you've verified the MP4 output plays correctly on your target devices.
Use MP4 for Web
If you're converting for websites, MP4 with H.264 is the gold standard — supported by all browsers and ideal for HTML5 video.
AVI vs MP4 at a glance
| Feature | AVI | MP4 |
|---|---|---|
| Released | 1992 | 2001 |
| Compression | Less efficient | H.264 / H.265 |
| File Size | Large | 50–70% smaller |
| Video Quality | Good | Excellent |
| Universal Support | Limited | Universal |
| Streaming | Poor | Excellent |
| Subtitle Support | Limited | Full (SRT, VTT) |
| Best For | Legacy systems | Everything |
AVI to MP4 — Frequently Asked Questions
Yes, completely free with no limits. Convert as many AVI files to MP4 as you need — no daily caps, no signup, no watermarks. Convertly is 100% free, supported by ads and optional donations.
No. Convertly processes all AVI to MP4 conversions entirely in your browser using client-side JavaScript and WebCodecs API. Your videos never leave your device, ensuring complete privacy.
MP4 uses efficient H.264 or H.265 compression, so file sizes are smaller while maintaining excellent quality. At high bitrate settings, the visual difference is virtually imperceptible. You can choose your preferred quality level before converting.
Yes. Convertly supports batch conversion — select multiple AVI files and convert them all to MP4 in one go. Each file is processed independently and downloaded separately or as a batch.
AVI (Audio Video Interleave) is a multimedia container format introduced by Microsoft in 1992. While it was revolutionary at the time, AVI lacks support for modern codecs, subtitles, and efficient compression. MP4 offers better quality at smaller sizes and is universally supported.
MP4 is the most universally supported video format. It works on all modern devices, browsers, and platforms. AVI files are often large, incompatible with mobile devices, and unsupported by many modern media players and web platforms.
MP4 files are typically 50–70% smaller than the equivalent AVI file at the same visual quality. This is because MP4 uses advanced compression (H.264/H.265) while AVI often uses older, less efficient codecs.
Yes. MP4 is the standard video format for both iOS and Android. Your converted MP4 files will play natively in any mobile media player, browser, or social media app without additional software.
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