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GPT-4o mini vs GLM-5.3-Flash

Detailed pricing comparison and cost analysis.

Updated September 2026

Cost Simulator

GPT-4o mini Cost
$0.27
GLM-5.3-Flash Cost
$0.13
GLM-5.3-Flash is 54% cheaper
FeatureGPT-4o miniGLM-5.3-Flash
ProviderOpenAIZhipu AI
Input Price (1M)$0.15$0.07
Output Price (1M)$0.60$0.25
Context Window128,0001,000,000

Verdict

GPT-4o mini costs $0.15 per 1M input tokens and $0.60 per 1M output tokens. GLM-5.3-Flash costs $0.07 per 1M input tokens and $0.25 per 1M output tokens. GLM-5.3-Flash is 50% cheaper on input tokens than GPT-4o mini. For output tokens, GLM-5.3-Flash is the more affordable option at $0.25/1M vs $0.60.

On context window, GLM-5.3-Flash supports 1,000,000 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-4o mini

  • ✓ You are already integrated with OpenAI

When to choose GLM-5.3-Flash

  • ✓ You need the lowest input token cost ($ 0.07/1M)
  • ✓ Your workload is output-heavy — GLM-5.3-Flash generates text cheaper
  • ✓ You need a larger context window (1,000,000 tokens)
  • ✓ 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-4o mini cheaper than GLM-5.3-Flash?

GLM-5.3-Flash is cheaper on input tokens at $0.07/1M vs $0.15/1M for GPT-4o mini — a 50% saving.

What is the context window of GPT-4o mini vs GLM-5.3-Flash?

GPT-4o mini has a 128,000-token context window. GLM-5.3-Flash has a 1,000,000-token context window. GLM-5.3-Flash supports the larger context, suitable for longer documents and agentic workflows.

Which model is better: GPT-4o mini or GLM-5.3-Flash?

The best choice depends on your use case. For cost efficiency on input tokens, GLM-5.3-Flash is the cheaper option. For maximum context length, GLM-5.3-Flash supports 1,000,000 tokens. Use the comparison table above to find the right fit for your workload.