Standard Compute
Model comparison 2026

Claude Sonnet 5.5 vs Kimi K2.6

Claude Sonnet 5.5
Anthropic · Balanced · Proprietary
$4.40/1M · 1M ctx
Kimi K2.6
Moonshot AI · Frontier · Open weights
$1.48/1M · 262K ctx

Community vote

Pick a winner in each dimension. You can change your vote any time.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for money
How much capability you get per dollar
Reliability
Consistent results: fewer refusals, loops and format breaks

Specs and pricing side by side

Spec
Sonnet 5.5
Kimi K2.6
Maker
Anthropic
Moonshot AI
Blended price / 1M
$4.40
$1.48
Input / output
$2.00 in · $10 out / 1M tokens
$0.65 in · $3.41 out / 1M tokens
Context window
1M
262K
Open weights
No
Yes
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
9.8
8.6
Agentic Ability
9.8
8.8
Speed
8.4
7.6
Value for money
8.8
9.2
Reliability
9.4
9.0

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: Sonnet 5.5 or Kimi K2.6?

Updated 2026-10-13

Choose Claude Sonnet 5.5 if you want the everyday default for coding agents, escalating to Opus 5.5 only for the hardest tasks. Choose Kimi K2.6 if you want a flagship-feel open-weight generalist.

In our editorial scoring, Claude Sonnet 5.5 leads in 4 of five dimensions (output quality, agentic ability, speed and reliability), while Kimi K2.6 leads in 1. On price, Claude Sonnet 5.5 runs about $4.40 per 1M tokens (blended) and is proprietary; Kimi K2.6 is about $1.48 and open-weight.

Where Sonnet 5.5 falls short
  • Artificial Analysis flags it as very verbose, which adds output tokens
  • Released September 2026, so its long-run track record is still short
Full Sonnet 5.5 breakdown →
Where Kimi K2.6 falls short
  • A step behind the closed flagships
  • Pricier than the cheapest open models
Full Kimi K2.6 breakdown →

The agent matters as much as the model. Compare AI agents →

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