Editing video with Runway Aleph 2

Updated 2026-10-02

Generation models create new footage; an editing model transforms footage you already have. Runway's Aleph 2 is the latter.

Request shape

Send model: "runway/aleph-2", a non-empty prompt describing the edit, and input_video_url pointing to a public clip. The field is mutually exclusive with start-image and reference inputs.

Limits

• Input clips are capped at 30 seconds.
• Output length follows the input.
• Billing follows the input duration, so trim clips before submitting.

Prompting edits

Describe the change, not the whole scene: "change the weather to heavy rain", "replace the car with a red pickup truck", "convert to watercolor animation". Keep one major change per request for the most predictable results.

Try generation first

If you do not yet have footage, generate with runway/gen-4.5 (see the quickstart) or compare other models on the pricing page.