Claude Opus 5 vs Kimi K3
Both are Flagship-tier models, from Anthropic and Moonshot AI respectively. Kimi K3 is the cheaper choice overall at a 4:1 input:output ratio.
Which is cheaper
Side by side
| Spec | Claude Opus 5 | Kimi K3 |
|---|---|---|
| Provider | Anthropic | Moonshot AI |
| Tier | Flagship | Flagship |
| Context window | 1M | 1.05M |
| Max output | 128K | — |
| Input $/1M | $5.00 | $3.00 |
| Output $/1M | $25.00 | $15.00 |
| Cache read $/1M | $0.50 | $0.30 |
| Cache write $/1M | $6.25 | — |
| Modalities | text, image | text |
Claude Opus 5. 5-minute cache write shown ($6.25 = 1.25x base input); 1-hour cache write is $10/MTok (2x base). Batch API is 50% off ($2.50/$12.50). Context window and max output cross-checked against platform.claude.com/docs/en/about-claude/models/overview.
Kimi K3. input is cache-miss (standard) price per 1M tokens; cache_read is cache-hit price ($0.30).
Sources
Claude Opus 5 — verified August 29, 2026
Kimi K3 — verified August 29, 2026
Full Claude Opus 5 pricing page → · Full Kimi K3 pricing page →