How to Upload & Optimize Reddit Videos | Best Formats & Compression
Reddit API Documentation & Encoding Limitations
Introduction
The Reddit API allows developers to upload, process, and retrieve videos, but it comes with strict encoding limitations that can cause compatibility issues. Understanding how Reddit handles video formats, compression, and API rate limits is crucial for developers, content creators, and automation engineers.
This guide covers:
✅ Supported video formats & encoding restrictions
✅ Reddit’s API endpoints for media uploads
✅ Troubleshooting API rate limits & compression issues
✅ FFmpeg & HandBrake commands for optimizing Reddit videos
1. Supported Video Formats & Encoding Restrictions
Reddit only accepts MP4 (H.264) with AAC audio. Unsupported formats are re-encoded, leading to potential quality loss.
| Format | Codec | Audio | Supported? | Compression Applied? |
|---|---|---|---|---|
| MP4 | H.264 | AAC | ✅ Yes | ✅ Yes (Reddit re-encodes) |
| WebM | VP8/VP9 | Opus | ❌ No | ❌ Not supported |
| MOV | H.264 | AAC | ❌ No | ❌ Must convert to MP4 |
| AVI | DivX/Xvid | MP3 | ❌ No | ❌ Must convert to MP4 |
🔹 Key Encoding Constraints:
- Max file size: 1GB
- Max resolution: 1080p (Higher resolutions get downscaled)
- Max frame rate: 30fps (Higher fps gets capped)
- Bitrate: Dynamic compression applied
📌 Why It Matters: If your video doesn’t match these specs, Reddit will re-encode it with aggressive compression, causing blurry visuals and lower quality audio.
2. Reddit API Media Upload Process
Reddit’s API has a multi-step upload process using media_asset_upload_request. Here’s how it works:
Step 1: Request an Upload URL
jsonCopyEditPOST https://www.reddit.com/api/media_asset_upload_request
{
"filepath": "video.mp4",
"mimetype": "video/mp4"
}
🔹 Returns a signed S3 URL to upload your video.
Step 2: Upload the Video to the Signed URL
Use cURL or Python to upload the video:
bashCopyEditcurl -X PUT -H "Content-Type: video/mp4" --data-binary "@video.mp4" "SIGNED_URL"
Step 3: Submit the Video Post
jsonCopyEditPOST https://www.reddit.com/api/submit
{
"kind": "video",
"url": "MEDIA_ASSET_URL",
"title": "My Reddit Video",
"sr": "subreddit_name"
}
3. Encoding Limitations & How Reddit Compresses Videos
Reddit applies automatic compression to all uploaded videos.
| Factor | Impact | Solution |
|---|---|---|
| Bitrate Reduction | Videos are compressed aggressively | Upload at higher bitrate (4-6 Mbps) to retain quality |
| Resolution Downscaling | 4K & 2K videos are downscaled to 1080p | Upload at 1080p max to avoid quality loss |
| Frame Rate Cap | Reddit limits fps to 30fps | Manually convert to 30fps before upload |
| Audio Compression | AAC audio may be compressed further | Use 128kbps+ AAC to maintain clarity |
📌 Best Practices for High-Quality Uploads:
✅ Use MP4 (H.264) + AAC audio
✅ Upload at 1080p (not 4K) to avoid excessive compression
✅ Maintain a bitrate of 4-6 Mbps
✅ Manually set frame rate to 30fps before upload
4. How to Optimize Videos for Reddit Using FFmpeg & HandBrake
If your video does not meet Reddit’s encoding standards, use FFmpeg or HandBrake to convert & optimize it before upload.
FFmpeg Command for Optimizing Reddit Videos
bashCopyEditffmpeg -i input.mp4 -c:v libx264 -crf 23 -preset fast -c:a aac -b:a 128k output.mp4
🔹 Breakdown of Parameters:
-crf 23→ Balances file size & quality-preset fast→ Optimized for quick encoding-b:a 128k→ Maintains decent audio quality
HandBrake Settings for Reddit Video Uploads
- Select MP4 format
- Codec: H.264 + AAC audio
- RF Value: 22-24 for best compression
- Enable Web Optimized for better playback
5. Reddit API Rate Limits & Workarounds
Reddit enforces rate limits on video uploads to prevent spam.
| API Limit | Restriction | Workaround |
|---|---|---|
| Uploads per hour | Max 5 per user | Use multiple accounts with unique API keys |
| Max request size | 1GB per file | Split videos into smaller chunks |
| API call frequency | Limited requests per min | Add delays (sleep timers) in scripts |
6. Common Reddit API Video Upload Errors & Fixes
| Error | Cause | Solution |
|---|---|---|
"Media type not supported" | Wrong format (e.g., WebM, MOV) | Convert to MP4 (H.264 + AAC) |
"File too large" | Exceeds 1GB limit | Compress using FFmpeg or HandBrake |
"Upload URL expired" | Delay in using signed URL | Regenerate a new upload URL |
"Rate limit exceeded" | Too many requests | Wait 15-30 mins before retrying |