GPT-5.6 Terra vs GLM-5.2 — LLM API Cost Comparison
Compare GPT-5.6 Terra (OpenAI) vs GLM-5.2 (Zhipu AI (GLM)) on cost per million tokens, context window, and monthly spend.
Prices verified 2026-08-03 · Pricing may change — use the calculator for current estimates
- Input
- $2/1M tokens
- Output
- $12/1M tokens
- Context
- 1M tokens
- Released
- 2026-07
OpenAI balanced GPT-5.6 tier; 1.05M context
- Input
- $8/1M tokens
- Output
- $28/1M tokens
- Context
- 1M tokens
- Released
- 2026-06
Latest Zhipu flagship; 1M context and 128K maximum output
Monthly Cost by Usage Tier (70% input / 30% output ratio)
| Usage | GPT-5.6 Terra | GLM-5.2 | Cheaper by |
|---|---|---|---|
| Light (1M tokens) | $5.00 | $14.00 | GPT-5.6 Terra (64%) |
| Moderate (10M tokens) | $50.00 | $140 | GPT-5.6 Terra (64%) |
| Heavy (100M tokens) | $500 | $1,400 | GPT-5.6 Terra (64%) |
| Very Heavy (1B tokens) | $5,000 | $14,000 | GPT-5.6 Terra (64%) |
Frequently Asked Questions
Which is cheaper — GPT-5.6 Terra or GLM-5.2?
For input tokens, GPT-5.6 Terra is cheaper at $2/1M tokens — 4.0× less than $8/1M. For output tokens, GPT-5.6 Terra wins at $12/1M vs $28/1M. At heavy workloads (100M tokens/month), the cost difference can be significant.
What is the context window difference between GPT-5.6 Terra and GLM-5.2?
GPT-5.6 Terra supports 1,050,000 tokens per request; GLM-5.2 supports 1,000,000 tokens. GPT-5.6 Terra wins on context length, making it better for long documents, large codebases, or extended conversations without chunking.
When should I choose GPT-5.6 Terra over GLM-5.2?
Choose GPT-5.6 Terra (OpenAI) if you prefer OpenAI's ecosystem, tooling, or reliability track record. OpenAI balanced GPT-5.6 tier; 1.05M context. Choose GLM-5.2 (Zhipu AI (GLM)) if Latest Zhipu flagship; 1M context and 128K maximum output. 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 GPT-5.6 Terra vs GLM-5.2?
At 700M input + 300M output tokens (1B total): GPT-5.6 Terra costs $5000; GLM-5.2 costs $14000. The difference is $9000/billion tokens at this 70/30 input/output ratio.