threads.media.video_size_max - letmepost.dev

What it checks

byteLength <= 1_000_000_000 per video.

Why

Meta’s Threads docs cap per-video at 1 GB on the create-container endpoint. Beyond that the upstream rejects before the post becomes visible.

Failure response

{
  "error": {
    "code": "preflight_failed",
    "rule": "threads.media.video_size_max",
    "platform": "threads",
    "message": "Video is 1450000000 bytes; Threads allows at most 1000000000.",
    "remediation": "Compress the video under 1000000000 bytes (Threads's per-video limit is 1 GB)."
  }
}

Remediation

Re-encode at a lower bitrate or split the post. For 1080p, 6 Mbps is a generous ceiling:

ffmpeg -i input.mp4 -c:v libx264 -b:v 6M -c:a aac -b:a 128k -movflags +faststart output.mp4

threads.media.image_size_max