Luma AI API vs Runway API

Luma AI API

Dollar prices per clip, $0.30 for 5 seconds at 720p, no credits to convert. Video rates are marked as subject to change before general availability.

Runway API

OpenAPI 3.1, llms.txt and Markdown copies of every docs page. Gen-3 Alpha Turbo and Gen-4 Aleph were removed on 2026-07-30 with no prior notice in the changelog.

Luma AI API

1. Send model ray-3.2 and type video, with resolution and duration inside video. Older model names are rejected
2. Poll GET /v1/generations/{id} until completed or failed, then copy the presigned URL
3. On 429, read detail. Rate limit exceeded means wait Retry-After, Too many concurrent jobs means wait for a job to finish
4. Use keyframes with keyframe_indexes for 10 second clips. start_frame and end_frame only work at 5 seconds

Runway API

1. Send X-Runway-Version: 2024-11-06 on every request or it fails
2. Use the SDK's wait-for-output helper or poll GET /v1/tasks/{id} until SUCCEEDED or FAILED
3. Don't retry a SAFETY.* failure unchanged. It's moderation, not an outage
4. Take model IDs from the models page, not memory. Two were removed without notice on 2026-07-30
5. Copy outputs to your own storage. URLs expire within 24 to 48 hours