GLM-5.1 vs Claude Sonnet 4.6 — LLM API Cost Comparison
Compare GLM-5.1 (Zhipu AI (GLM)) vs Claude Sonnet 4.6 (Anthropic) on cost per million tokens, context window, and monthly spend.
Prices verified 2026-05-23 · Pricing may change — use the calculator for current estimates
- Input
- $1.4/1M tokens
- Output
- $4.4/1M tokens
- Context
- 205K tokens
- Released
- 2026-03
Latest GLM flagship; improved reasoning over GLM-5
- Input
- $3/1M tokens
- Output
- $15/1M tokens
- Context
- 1M tokens
- Released
- 2026-04
Best speed/intelligence balance; extended thinking supported
Monthly Cost by Usage Tier (70% input / 30% output ratio)
| Usage | GLM-5.1 | Claude Sonnet 4.6 | Cheaper by |
|---|---|---|---|
| Light (1M tokens) | $2.30 | $6.60 | GLM-5.1 (65%) |
| Moderate (10M tokens) | $23.00 | $66.00 | GLM-5.1 (65%) |
| Heavy (100M tokens) | $230 | $660 | GLM-5.1 (65%) |
| Very Heavy (1B tokens) | $2,300 | $6,600 | GLM-5.1 (65%) |
Frequently Asked Questions
Which is cheaper — GLM-5.1 or Claude Sonnet 4.6?
For input tokens, GLM-5.1 is cheaper at $1.4/1M tokens — 2.1× less than $3/1M. For output tokens, GLM-5.1 wins at $4.4/1M vs $15/1M. At heavy workloads (100M tokens/month), the cost difference can be significant.
What is the context window difference between GLM-5.1 and Claude Sonnet 4.6?
GLM-5.1 supports 204,800 tokens per request; Claude Sonnet 4.6 supports 1,000,000 tokens. Claude Sonnet 4.6 wins on context length, making it better for long documents, large codebases, or extended conversations without chunking.
When should I choose GLM-5.1 over Claude Sonnet 4.6?
Choose GLM-5.1 (Zhipu AI (GLM)) if you prefer Zhipu AI (GLM)'s ecosystem, tooling, or reliability track record. Latest GLM flagship; improved reasoning over GLM-5. Choose Claude Sonnet 4.6 (Anthropic) if Best speed/intelligence balance; extended thinking supported. the price/performance fits your workload better. Use this calculator to find the break-even point for your exact token volume.
How much does 1 billion tokens cost on GLM-5.1 vs Claude Sonnet 4.6?
At 700M input + 300M output tokens (1B total): GLM-5.1 costs $2300; Claude Sonnet 4.6 costs $6600. The difference is $4300/billion tokens at this 70/30 input/output ratio.