{"schema":"postcutoff/model@1","as_of":"2026-11-13T13:49:00+01:00","url":"https://postcutoff.com/m/runway-gen-4-5/","md":"https://postcutoff.com/m/runway-gen-4-5/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"human editor","policy":"https://postcutoff.com/about/"},"license":null,"id":"runway-gen-4-5","name":"Runway Gen-4.5","org":"Runway","family":"Gen-4","released":"2025-12-01","status":"current","type":"video-gen","modality_in":["text","image"],"modality_out":["video"],"open_weights":false,"model_license":"proprietary","context_window":null,"max_output":null,"knowledge_cutoff":null,"pricing":{"per_second":0.12,"unit":"per second of video (12 credits/s at $0.01/credit; pro/HDR formats extra)","source":"https://docs.dev.runwayml.com/guides/pricing/"},"price_line":"$0.12 per second","access":[{"provider":"Runway API","model_id":"gen4.5","endpoint":"https://api.dev.runwayml.com/v1/image_to_video","docs":"https://docs.dev.runwayml.com/guides/models/"},{"provider":"Web app","url":"https://app.runwayml.com"}],"capabilities":[{"name":"#1 on Artificial Analysis text-to-video at launch","detail":"Launched as the top model on the Artificial Analysis Text-to-Video leaderboard (1,247 Elo), with better physics (liquids, momentum, collisions).","first":false,"discovered":"launch","source":"https://runway.com/research/introducing-runway-gen-4.5"},{"name":"HDR and professional output formats","detail":"API can output ProRes, PNG/EXR sequences, 10-bit SDR and HDR10/HLG/ACEScg masters (Gen-4.5 only for HDR).","first":false,"discovered":"later","source":"https://docs.dev.runwayml.com/guides/models/"}],"entry":null,"notes":"Announced 2025-12-01; added to Runway API 2026-02-10 (text-to-video and image-to-video, 2-10 s). Cheaper sibling gen4_turbo (5 credits/s). gen4_aleph and gen3a_turbo removed from API 2026-07-30. Requires header X-Runway-Version: 2024-11-06.","verified":"2026-09-29","body_md":"Runway's flagship text/image-to-video model. Runway's API also resells third-party models (Veo, Seedance, etc.).\n\n```bash\ncurl -X POST https://api.dev.runwayml.com/v1/image_to_video -H \"Authorization: Bearer $RUNWAYML_API_SECRET\" \\\n  -H \"X-Runway-Version: 2024-11-06\" -H \"Content-Type: application/json\" \\\n  -d '{\"model\":\"gen4.5\",\"promptText\":\"a drone shot over a misty fjord\",\"ratio\":\"1280:720\",\"duration\":5}'\n# poll GET https://api.dev.runwayml.com/v1/tasks/{id}\n```\n\nSources: https://docs.dev.runwayml.com/guides/models/ , https://docs.dev.runwayml.com/guides/pricing/ , https://docs.dev.runwayml.com/api-details/api_changelog/ , https://runway.com/research/introducing-runway-gen-4.5","page_url":"https://postcutoff.com/m/runway-gen-4-5/","standing":{"kind":"video generation","newer_count":17,"newer":[{"id":"gemini-omni-1-2-flash","name":"Gemini Omni 1.2 Flash","org":"Google DeepMind","released":"2026-11-05","page_url":"https://postcutoff.com/m/gemini-omni-1-2-flash/"},{"id":"flux-3-max","name":"FLUX 3 Max","org":"Black Forest Labs","released":"2026-10-19","page_url":"https://postcutoff.com/m/flux-3-max/"},{"id":"kling-4-0","name":"Kling 4.0 (and 4.0 Flash)","org":"Kuaishou","released":"2026-10-15","page_url":"https://postcutoff.com/m/kling-4-0/"},{"id":"tavus-griffin","name":"Tavus Griffin (Human Interaction Model)","org":"Tavus","released":"2026-10-01","page_url":"https://postcutoff.com/m/tavus-griffin/"},{"id":"heygen-video-1","name":"HeyGen Video 1","org":"HeyGen","released":"2026-09-30","page_url":"https://postcutoff.com/m/heygen-video-1/"}],"before":null,"after":{"id":"runway-aleph-2","name":"Runway Aleph 2.0","org":"Runway","released":"2026-05-21","page_url":"https://postcutoff.com/m/runway-aleph-2/"},"weights":"closed","licence":"proprietary","licence_permissive":false,"summary":"Closed weights; access is hosted only."}}