GLM-5.3-Flash versus Kimi K2.6

What are we comparing?

GLM-5.3-Flash and Kimi K2.6 are two open-weight models that you can install on your own servers, one from Zhipu AI (Z.ai), the other from Moonshot AI. GLM-5.3-Flash was released on September 18, 2026, Kimi K2.6 on April 20, 2026.

All figures below come from public sources checked on October 22, 2026: models.dev and OpenRouter for prices and capabilities, Epoch AI for scores.

Which one is more capable?

On our capability index, GLM-5.3-Flash scores 71.9 out of 100 and Kimi K2.6 84.4. Kimi K2.6 leads by 12.5 points.

On the 3 benchmarks reported for both, GLM-5.3-Flash wins 0 times and Kimi K2.6 3:

• GPQA Diamond (PhD-level science questions): GLM-5.3-Flash 90.2%, Kimi K2.6 90.8%
• OTIS Mock AIME (competition mathematics problems): GLM-5.3-Flash 93.9%, Kimi K2.6 96.1%
• FrontierMath (very hard research-level mathematics): GLM-5.3-Flash 55.8%, Kimi K2.6 57.2%

Pricing

GLM-5.3-Flash costs $0.30 per million input tokens and $1.05 per million output tokens; Kimi K2.6 costs $0.95 and $4.

For a typical agent task (read 20,000 tokens, write 2,000), expect $0.008 with GLM-5.3-Flash versus $0.027 with Kimi K2.6. GLM-5.3-Flash is 3.3 times cheaper, a gap that adds up quickly over 1,000 tasks: $18.93 difference.

Run the numbers with your own volumes in the agent cost calculator.

Features and limits

GLM-5.3-Flash reads more in one go: 1,000,000 tokens of context (roughly 1,500 pages), versus 262,144 for Kimi K2.6.

Reasoning mode: GLM-5.3-Flash yes, Kimi K2.6 yes. Tool calling: GLM-5.3-Flash yes, Kimi K2.6 yes. Image input: GLM-5.3-Flash yes, Kimi K2.6 yes.

Both publish their weights: you can host them yourself.

In short

Our reading of the data:

• Choose GLM-5.3-Flash for a lower cost, a larger context window and a more recent release.
• Choose Kimi K2.6 for a higher capability index.

This verdict relies on public figures; it does not replace a trial on your own tasks.