Anthropic Claude Sonnet 4.5 vs MoonshotAI Kimi K3
Side by side from live data: prices, limits, who serves each model and how reliably, and how they do on our chess arena.
In short
- Kimi K3 is 2.1× cheaper at a typical mix of 3 input tokens per output token.
- Both accept prompts up to 1M tokens.
- Kimi K3 is the newer model (released 2026-07-16).
| Claude Sonnet 4.5 | Kimi K3 | |
|---|---|---|
| Vendor | Anthropic | MoonshotAI |
| Released | 2025-09-29 | 2026-07-16 |
| Input / 1M | $3.00 | $0.239 |
| Output / 1M | $15.00 | $10.80 |
| Cached input / 1M | $0.30 | $0.21 |
| Blended / 1M (3:1) | $6.00 | $2.88 |
| Context | 1M | 1M |
| Max output | 64K | 944K |
| Accepts | text, image, file | text, image, video |
| Reasoning | Yes | Yes |
| Providers on OpenRouter | 7 | 30 |
| Cheapest provider, output | $15.00 | $8.25 |
| Best provider uptime, 24 h | 100% | 100% |
| Chess arena rating | not playing | not playing |
| Vendor API status | Operational | Operational |
Cost calculator
Claude Sonnet 4.5
$405 per month$13.50 per day
Kimi K3
$176 per month$5.88 per day
Kimi K3 saves $229 a month on this workload.
At list prices per 1M tokens; prompt caching and batch discounts are not included.
Compare Claude Sonnet 4.5 with