Instagram Reels is one of the most reach-generating content formats on the platform right now — but upload the wrong format or wrong aspect ratio and Instagram either crops your video awkwardly, compresses it visibly, or rejects it outright. This guide covers every spec Instagram wants for Reels, what happens when you deviate, and how to prep any video for Reels free using browser-based tools.
Instagram Reels: Quick-Reference Specs
| Setting | Recommended | Notes |
|---|---|---|
| Format | MP4 (H.264) | MOV also accepted; MP4 most reliable |
| Aspect ratio | 9:16 (vertical) | 1080 × 1920px ideal; 4:5 also works for feed crosspost |
| Resolution | 1080 × 1920px | Minimum 500px wide |
| Frame rate | 30fps | 23–60fps accepted; keep source frame rate |
| Max length | 90 seconds | 3 seconds minimum |
| Max file size | 1 GB | Instagram re-encodes on upload |
| Audio codec | AAC, 128 kbps+ | Stereo preferred |
| Safe zone | Keep text/faces above 35% from bottom | UI overlays cover lower portion of screen |
Converting a Horizontal Video for Reels
Most cameras and screen recorders shoot 16:9 horizontal. If you want to repurpose that content as a Reel, the aspect ratio conversion (adding black bars or cropping to vertical) requires a full video editor. What VideoToolShack's free browser tools handle well is everything else in the prep workflow:
- Trim to 90 seconds or under — use the Video Trimmer to cut your clip to the strongest 90-second segment.
- Convert to MP4 — if your source is MOV, WebM, or AVI, run it through the Format Converter first.
- Compress if over 1 GB — use the Video Compressor to bring large files under Instagram's limit.
- Add subtitles — burn in captions with the Add Subtitles tool. Reels auto-captions are unreliable; burned-in captions are guaranteed.
- Add a watermark/logo — brand your Reel before posting using the Add Watermark tool.
The Safe Zone: Don't Ignore It
Instagram's Reels UI overlays buttons, your username, caption, and audio attribution across the bottom 35% of the screen. Anything important — your face, a product, key text — needs to be in the upper 65% of the frame. Even if your video looks perfect on your phone in preview, the live Reels player will cover up anything in that lower zone for viewers.
Quality After Instagram's Re-Encoding
Instagram re-encodes every uploaded video, which means some quality loss is unavoidable. You can minimise it by:
- Uploading at 1080 × 1920 (not higher, not lower) — Instagram's encoder is optimised for this resolution
- Keeping your source bitrate at 3.5 Mbps or higher before upload — giving Instagram a better source to work from
- Not pre-compressing heavily — every compression stage stacks quality loss; let Instagram do its own compression on a high-quality source
- Uploading via the app on a fast connection — Instagram's web uploader sometimes produces lower-quality encodes than the mobile app
Reels vs. Instagram Feed Video: Key Differences
Reels (9:16, up to 90s) and feed videos (4:5 or 1:1, up to 60s for standard posts) have different specs. If you want a clip to appear in both the Reels tab and the feed, the safest approach is to film 9:16 vertical and let Instagram handle the feed cropping — or produce two cuts optimised for each placement separately.