Runway vs StepFun: Token Pricing, Speed & Intelligence
Full comparison of Runway and StepFun — live token pricing, latency, throughput, context window, strengths, weaknesses, and best use cases. Rates sourced from public APIs — verify before use.
Runway
Gen-4 video generation API — cinematic quality text-to-video and image-to-video
Runway is a creative AI company best known for its Gen series of video generation models. Gen-4 and Gen-4 Turbo are available via API, producing cinematic-quality video from text or image prompts. Runway is widely used in professional film and advertising production. Pricing is per second of generated video.
StepFun
Step-5 — Chinese frontier LLM with strong multimodal and reasoning capability
StepFun is a Chinese AI startup developing the Step model series. Step-5 Preview is the frontier tier, competing with top Chinese and international models on reasoning and multimodal benchmarks. Step-3.7 Flash is the efficient tier for cost-sensitive workloads. StepFun is backed by Tencent and focuses on enterprise and developer API access.
Key metric comparison
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Live token pricing
Strengths and weaknesses
Runway
StepFun
Key differentiators
Gen-4 is Runway's cinematic-quality video generation model, trusted by professional film and advertising studios — with Gen-4 Turbo offering a faster, lower-cost alternative via the same API.
Step-5 is StepFun's frontier reasoning model with multimodal capability, backed by Tencent — positioned as a competitive alternative to Qwen and ERNIE for Chinese enterprise workloads.
Frequently asked questions
Runway FAQs
How is Runway priced?
Runway charges per second of generated video. Gen-4 is $0.100/second and Gen-4 Turbo is $0.050/second. See runwayml.com/pricing for current rates.
What is Gen-4?
Gen-4 is Runway's latest video generation model, producing cinematic-quality output from text or image prompts. It is used in professional film, advertising, and visual effects production.
What is the difference between Gen-4 and Gen-4 Turbo?
Gen-4 produces higher-quality output at $0.100/second. Gen-4 Turbo is faster and cheaper at $0.050/second, with slightly lower quality. Both support text-to-video and image-to-video generation.
StepFun FAQs
What is StepFun?
StepFun is a Chinese AI startup backed by Tencent, developing the Step model series. Step-5 Preview is the frontier tier and Step-3.7 Flash is the efficient tier, both available via the StepFun API.
How much does the StepFun API cost?
Step-5 Preview is $1.00/$2.70 per 1M input/output tokens. Step-3.7 Flash is $0.20/$1.15 per 1M tokens. See platform.stepfun.com/docs/pricing for current rates.
Does Step-5 support multimodal input?
Yes. Step-5 Preview supports text, image, and video understanding in a single API call, making it suitable for multimodal enterprise applications.
Provider resources
Runway — Gen-4 video generation API — cinematic quality text-to-video and image-to-video
Runway is a creative AI company best known for its Gen series of video generation models. Gen-4 and Gen-4 Turbo are available via API, producing cinematic-quality video from text or image prompts. Runway is widely used in professional film and advertising production. Pricing is per second of generated video.
Gen-4 is Runway's cinematic-quality video generation model, trusted by professional film and advertising studios — with Gen-4 Turbo offering a faster, lower-cost alternative via the same API.
StepFun — Step-5 — Chinese frontier LLM with strong multimodal and reasoning capability
StepFun is a Chinese AI startup developing the Step model series. Step-5 Preview is the frontier tier, competing with top Chinese and international models on reasoning and multimodal benchmarks. Step-3.7 Flash is the efficient tier for cost-sensitive workloads. StepFun is backed by Tencent and focuses on enterprise and developer API access.
Step-5 is StepFun's frontier reasoning model with multimodal capability, backed by Tencent — positioned as a competitive alternative to Qwen and ERNIE for Chinese enterprise workloads.
Key strengths compared
Runway
- Gen-4 produces cinematic-quality video used in professional film and advertising
- Gen-4 Turbo at $0.050/second offers faster generation at lower cost
- Strong motion quality and temporal consistency
- Video generation only — no text, image, or audio LLM models
- Gen-4 at $0.100/second is among the higher-priced video generation APIs
StepFun
- Step-5 Preview is competitive with top Chinese frontier models on reasoning benchmarks
- Step-3.7 Flash at $0.20/$1.15 per 1M tokens offers strong value for efficient inference
- Multimodal capability on Step-5 (text, image, video understanding)
- Newer entrant — smaller track record than established frontier labs
- Documentation and support primarily in Chinese
Key weaknesses compared
Runway
- Video generation only — no text, image, or audio LLM models
- Gen-4 at $0.100/second is among the higher-priced video generation APIs
- Generation latency is higher than text inference
StepFun
- Newer entrant — smaller track record than established frontier labs
- Documentation and support primarily in Chinese
- Limited international ecosystem and third-party integrations
Provider category context
Runway is a frontier lab, founded in 2018. StepFun is a frontier lab, founded in 2023. Both are frontier lab providers — the comparison is primarily about pricing, model selection, and feature differentiation within the same tier.
How to choose between them
Both Runway and StepFun are frontier labs with proprietary models. Choose based on benchmark performance for your specific task: Runway leads on gen-4 produces cinematic-quality video used in professional film and advertising, while StepFun leads on step-5 preview is competitive with top chinese frontier models on reasoning benchmarks. For cost-sensitive workloads, compare the cheapest model tier from each provider in the pricing table above — the gap between efficient-tier models is often larger than between flagship models.