The moment you need a model that can write, debug, and refactor code on the fly, the token budget splits cleanly: Kimi K2 charges $0.57 per 1M input tokens and $2.3 per 1M output tokens, while Claude Sonnet‑5 asks $2 for every million input tokens and $10 for output. That raw contrast alone makes Moonshot’s K2 look like the budget‑friendlier choice for heavy‑input workloads.
### How the two stacks break down per token
| Vendor | Model | Input | Cached Input | Output |
|--------|-------|-------|--------------|--------|
| Moonshot AI | kimi‑k2 | $0.57 | – | $2.3 |
| Anthropic | claude‑sonnet‑5 | $2 | $0.2 | $10 |
Kimi K2’s input price is less than a third of Claude Sonnet’s, and its output rate is roughly a quarter of the Anthropic offering. The disparity widens if you can cache prompts: Moonshot’s cached‑input rate for the K2‑thinking line sits at $0.6 for input and $0.15 for cached input, still far below the $0.2 cached‑input cost Anthropic tacks on to its Sonnet line. For pure code generation, the output cost dominates, and K2’s $2.3 per 1M output tokens is a decisive saving compared with Sonnet’s $10.
Both providers lock you into usage‑based billing, so there’s no hidden per‑seat surcharge. Moonshot also offers a cheaper “kimi‑k2.5” tier at $0.45 input and $2.25 output, which can shave another few cents per million tokens if you can tolerate the slightly older model. Anthropic’s cheapest Sonnet tier, “claude‑sonnet‑4”, is still $3 input and $15 output, making it the most expensive option on the table.
If you’re building an internal tool that will constantly ingest code snippets, prompts, and test cases, the input side of the bill will dominate, and Moonshot’s sub‑$1 input price gives you a comfortable margin. Conversely, if your workflow is output‑heavy—generating large codebases or detailed documentation—Claude Sonnet’s higher output rate can quickly eclipse any input savings. In practice, most agentic‑coding pipelines are balanced, so the combined per‑token cost is the decisive factor.
For startups that need to keep cloud spend low while still accessing a model capable of reasoning over code, Kimi K2 (or the even cheaper K2.5) is the clear pick. Larger enterprises that value Anthropic’s broader model ecosystem and are less sensitive to token spend may still gravitate toward Claude Sonnet, but they should expect a substantially higher bill for comparable workloads. In short, Moonshot delivers the cheaper per‑token economics across the board, making it the go‑to for cost‑conscious developers.
Pricing verified on 2026-09-12.