Compare AI tools

	Kling A	Replicate S	Claude Agent SDK S	Sora A
Tagline	Kuaishou's video model. The surprise standout.	Run any open-source AI model with an API call.	Anthropic's SDK for building your own agents on Claude.	OpenAI's video model. Long clips, cinematic quality.
Category	Video	Dev Platform	Agents	Video
Pricing	Credit-based, free trial	Pay per second of compute	API usage + SDK is free	Included with ChatGPT Plus/Pro
Best for	Anyone who wants top-tier video quality for less.	Developers using open-source models (Flux, SDXL, Whisper, etc).	Developers building custom agents for their own company/product.	ChatGPT subscribers experimenting with cinematic shots.
Strengths	Very strong motion + physics Often beats Runway on realism Great price	Tens of thousands of models (image, video, audio, LLMs) One-line API for any model Cog framework for custom model deploy	Production-grade agent primitives Built on Claude (best reasoning) Full control — build exactly what you need	Up to 20-sec clips at 1080p Strong physics + scene composition Storyboard feature for longer narratives Remix existing videos
Weaknesses	UX is rough for English speakers Queue times	Cold starts on less-popular models Pricing gets real at scale	Developer-only You build the UI	Stricter content policy than competitors Hit-or-miss on complex motion Text-in-video still struggles
Kai's verdict	A-tier. Rising fast. If you can tolerate the UX, quality per dollar is best-in-class.	S-tier for open-source model APIs. The default in this space.	S-tier for builders. The right primitives. What Kai is built on under the hood.	A-tier. Amazing when it works, frustrating when it doesn't. Runway still more reliable for pros.
Link	Open →	Open →	Open →	Open →