AI model APIs · head-to-head
Claude Sonnet 5 vs Kimi K3
Same usage, official rates, ranked by nothing but price. Both rate cards, the monthly bill at five workloads, and the exact usage mix where the answer flips.
The pricing verdict Claude Sonnet 5 is cheaper than Kimi K3 at every input:output mix — there is no usage pattern where Kimi K3 costs less.
Rate cards
| Per 1M tokens | Claude Sonnet 5 | Kimi K3 |
|---|---|---|
| Input | $2 | $3 |
| Cached input | $0.20 | $0.30 |
| Output | $10 | $15 |
| Context window | 1M | 1M |
Monthly cost at five workloads
| Workload | Tokens / month | Claude Sonnet 5 | Kimi K3 |
|---|---|---|---|
| Prototype | 1M in · 0.3M out | $5 | $7.50 |
| Small app | 10M in · 3M out | $50 | $75 |
| Production app | 50M in · 15M out | $250 | $375 |
| High volume | 200M in · 60M out | $1,000 | $1,500 |
| Heavy platform | 1B in · 300M out | $5,000 | $7,500 |
Standard on-demand rates from each provider's official pricing page, verified July 2026; figures exclude caching and batch discounts and any long-context surcharges. Claude Sonnet 5: These are the introductory rates Anthropic actually bills through Aug 31, 2026. Standard pricing of $3 in / $0.30 cached / $15 out takes effect Sept 1, 2026 — a 50% increase, so budget beyond August at the higher rate. Kimi K3: Cache-hit input bills at $0.30 per 1M. Price is one input — quality, latency and context limits differ. Confirm live pricing before committing.