GPT-5.4 Mini is $0.23 cheaper per 1M input tokens (23.5% lower; 1.31x difference).
API cost decision in 10 seconds
GLM 5.1 vs GPT-5.4 Mini
Pick GLM 5.1 for lower cost; pick GPT-5.4 Mini only if the larger context window matters more.
Pricing data updated:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick GLM 5.1 for lower cost; pick GPT-5.4 Mini only if the larger context window matters more.
On the standard 1M input plus 500K output workload, GLM 5.1 is estimated at $2.52 vs $3 for GPT-5.4 Mini, saving $0.48 (16% lower).
Cost-first pickGLM 5.1
Context-first pickGPT-5.4 Mini
Sample savings$0.4816%
10x traffic gap$4.8
GPT-5.4 Mini has more context, but GLM 5.1 saves $0.48 on the standard workload. At 10x that traffic, the same price gap is about $4.8. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Cost winner changes by workload shape: input-heavy / RAG favors GPT-5.4 Mini, balanced workload favors GLM 5.1, and output-heavy chatbot favors GLM 5.1.
| Workload shape | Token mix | Better pick | GLM 5.1 | GPT-5.4 Mini |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | GPT-5.4 Mini | $6.44 | $6 |
| Balanced workload | 1M input + 1M output | GLM 5.1 | $4.06 | $5.25 |
| Output-heavy chatbot | 1M input + 5M output | GLM 5.1 | $16.38 | $23.25 |
GLM 5.1 is $1.42 cheaper per 1M output tokens (31.6% lower; 1.46x difference).
GPT-5.4 Mini has 197.25K more context (1.97x larger).
GLM 5.1 is $0.48 cheaper on the standard workload (16% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
GPT-5.4 Mini has the lower input price; GLM 5.1 has the lower output price; GPT-5.4 Mini offers the larger context window. For the 1M input plus 500K output sample, GLM 5.1 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $2.52 for GLM 5.1 and $3 for GPT-5.4 Mini.
Choose GLM 5.1 when you care most about lower output-token price.
Choose GPT-5.4 Mini when you care most about lower input-token price, and larger context window.
- On the standard 1M input plus 500K output workload, GLM 5.1 is estimated at $2.52 vs $3 for GPT-5.4 Mini, saving $0.48 (16% lower).
- GLM 5.1 is $0.48 cheaper on the standard workload (16% lower).
- GPT-5.4 Mini is $0.23 cheaper per 1M input tokens (23.5% lower; 1.31x difference).
- GLM 5.1 is $1.42 cheaper per 1M output tokens (31.6% lower; 1.46x difference).
- GPT-5.4 Mini has 197.25K more context (1.97x larger).
| Feature | GLM 5.1 (Z.ai) | GPT-5.4 Mini (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.98 | $0.75 |
| Completion Price per 1M tokens | $3.08 | $4.5 |
| Sample Workload Cost 1M input + 500K output | $2.52 | $3 |
| Context Window | 202.75K | 400K |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | GLM 5.1 | On the standard 1M input plus 500K output workload, GLM 5.1 is estimated at $2.52 vs $3 for GPT-5.4 Mini, saving $0.48 (16% lower). |
| High-volume input processing | GPT-5.4 Mini | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | GLM 5.1 | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-5.4 Mini | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- GLM 4.5 Air (free) can replace GLM 5.1 when lower sample workload cost matters most: $0.
- GLM 4 32B can replace GLM 5.1 when lower sample workload cost matters most: $0.15.
- GLM 4.7 Flash can replace GLM 5.1 when lower sample workload cost matters most: $0.26.
- GLM 4.5 Air can replace GLM 5.1 when lower sample workload cost matters most: $0.55.
- Llama 4 Scout offers 10M context with $0.23 sample workload cost.
- Grok 4.20 offers 2M context with $2.5 sample workload cost.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- Gemini 3.1 Flash Lite offers 1.05M context with $1 sample workload cost.
- No popular competitor is currently available.
Cheaper alternatives
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