Claude Sonnet 5 vs Kimi K3
Anthropic vs Moonshot AI · Prices checked 12 August 2026
The two are closer than they look: Claude Sonnet 5 at $4.40 per million tokens blended, Kimi K3 at $6.60, a 33 per cent difference. A single 100K-input, 10K-output job costs $0.300 on Claude Sonnet 5 against $0.450 on Kimi K3.
On context, Kimi K3 is the larger at 1,049,000 tokens versus 1,000,000. Claude Sonnet 5 was released Jun 2026; Kimi K3 Jul 2026.
Pricing and capacity
| Metric | Claude Sonnet 5 | Kimi K3 | Difference |
|---|---|---|---|
| Input / 1M tokens | $2.00 | $3.00 | 33% |
| Output / 1M tokens | $10.00 | $15.00 | 33% |
| Blended · 70/30calculated | $4.40 | $6.60 | 33% |
| Blended · 50/50calculated | $6.00 | $9.00 | 33% |
| Blended · 80/20calculated | $3.60 | $5.40 | 33% |
| Blended · 20/80calculated | $8.40 | $12.60 | 33% |
| Job cost · 100K + 10Kcalculated | $0.300 | $0.450 | 33% |
| Job cost · 1M + 100Kcalculated | $3.00 | $4.50 | 33% |
| Context window | 1,000,000 | 1,049,000 | 5% |
Input and output rates are as published by each provider. Blended and job-cost rows are calculated comparison metrics, not published prices — how they are derived.
Benchmarks
These two models do not currently report scores on any of the same benchmark suites, so there is no like-for-like capability comparison to show. Rather than pad the page with one-sided numbers, the benchmark leaderboards list every score we do hold.
What each model is for
Claude Sonnet 5
Anthropic · Balanced
The most agentic Sonnet Anthropic has shipped: it plans, drives tools like browsers and terminals, and runs autonomously at a level that previously needed a larger model, with performance close to Opus 4.8 at a fraction of the price. Launch pricing is $2/$10 per MTok through 31 August 2026, after which it moves to $3/$15.
- Autonomous multi-step agent runs
- Browser and terminal tool use
- Near-Opus performance at Sonnet pricing
- 1M-token context
Kimi K3
Moonshot AI · Frontier
Moonshot AI's 2.7-trillion-parameter flagship, released in July 2026 as the largest open-weight model published to date and the first Chinese model widely treated as competitive with the top US frontier systems. It runs an always-on reasoning mode Moonshot calls "thinking mode", handles a 1M-token context window, and understands images natively. Two variants shipped: K3 Max for chat and agent work, K3 Swarm Max for large-scale parallel processing.
- Largest open-weight model released to date (2.7T parameters)
- Always-on "thinking mode" reasoning
- 1M-token context
- Native visual understanding
Frequently asked questions
Which is cheaper, Claude Sonnet 5 or Kimi K3?
The two are closer than they look: Claude Sonnet 5 at $4.40 per million tokens blended, Kimi K3 at $6.60, a 33 per cent difference. A single 100K-input, 10K-output job costs $0.300 on Claude Sonnet 5 against $0.450 on Kimi K3. Blended cost weights input at 70% and output at 30%; price your own token split for an exact answer, since the cheaper model on a blended basis is not always cheaper for your workload.
Which has the larger context window, Claude Sonnet 5 or Kimi K3?
On context, Kimi K3 is the larger at 1,049,000 tokens versus 1,000,000. The context window caps everything in a single request: prompt, retrieved documents, conversation history and the model’s own output all share it.
Can I compare Claude Sonnet 5 and Kimi K3 on my own numbers?
Yes. Open both in the side-by-side comparison tool to see every field at once, or use the token calculator to price your actual prompt and monthly request volume against each model. Both are free and need no sign-up.
Price it for your own workload
Related matchups
Terms used on this page
Prices and scores are recomputed on every deploy from the catalogue. Prices checked 12 August 2026.