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GPT-5.1 vs GLM-4.7

Detailed pricing comparison and cost analysis.

Updated September 2026

Cost Simulator

GPT-5.1 Cost
$3.25
GLM-4.7 Cost
$1.04
GLM-4.7 is 68% cheaper
FeatureGPT-5.1GLM-4.7
ProviderOpenAIZhipu AI
Input Price (1M)$1.25$0.60
Output Price (1M)$10.00$2.20
Context Window400,000204,800

Verdict

GPT-5.1 costs $1.25 per 1M input tokens and $10.00 per 1M output tokens. GLM-4.7 costs $0.60 per 1M input tokens and $2.20 per 1M output tokens. GLM-4.7 is 52% cheaper on input tokens than GPT-5.1. For output tokens, GLM-4.7 is the more affordable option at $2.20/1M vs $10.00.

On context window, GPT-5.1 supports 400,000 tokens — meaning it can fit more conversation history, documents, or code in a single request. This matters for RAG pipelines, long document analysis, and agentic workflows where context builds up over many turns.

When to choose GPT-5.1

  • ✓ You need a larger context window (400,000 tokens)
  • ✓ You are already integrated with OpenAI

When to choose GLM-4.7

  • ✓ You need the lowest input token cost ($ 0.60/1M)
  • ✓ Your workload is output-heavy — GLM-4.7 generates text cheaper
  • ✓ You are already integrated with Zhipu AI

Use the calculator above to simulate your specific workload and find the exact break-even point. For most applications, the cheapest model is the one that minimises your total monthly bill given your input-to-output token ratio.

Frequently Asked Questions

Is GPT-5.1 cheaper than GLM-4.7?

GLM-4.7 is cheaper on input tokens at $0.60/1M vs $1.25/1M for GPT-5.1 — a 52% saving.

What is the context window of GPT-5.1 vs GLM-4.7?

GPT-5.1 has a 400,000-token context window. GLM-4.7 has a 204,800-token context window. GPT-5.1 supports the larger context, suitable for longer documents and agentic workflows.

Which model is better: GPT-5.1 or GLM-4.7?

The best choice depends on your use case. For cost efficiency on input tokens, GLM-4.7 is the cheaper option. For maximum context length, GPT-5.1 supports 400,000 tokens. Use the comparison table above to find the right fit for your workload.