GPT-6 Luna is $2.7 cheaper per 1M input tokens (96.4% lower; 28x difference).
API cost decision in 10 seconds
NewGLM 5.3 Prime vs NewGPT-6 Luna
Pick GPT-6 Luna when budget and context both matter.
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Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick GPT-6 Luna when budget and context both matter.
On the standard 1M input plus 500K output workload, GPT-6 Luna is estimated at $0.35 vs $7.2 for GLM 5.3 Prime, saving $6.85 (95.1% lower).
Cost-first pickGPT-6 Luna
Context-first pickGPT-6 Luna
Sample savings$6.8595.1%
10x traffic gap$68.5
GPT-6 Luna is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $68.5. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
GPT-6 Luna stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | GLM 5.3 Prime | GPT-6 Luna |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | GPT-6 Luna | $18.4 | $0.75 |
| Balanced workload | 1M input + 1M output | GPT-6 Luna | $11.6 | $0.6 |
| Output-heavy chatbot | 1M input + 5M output | GPT-6 Luna | $46.8 | $2.6 |
GPT-6 Luna is $8.3 cheaper per 1M output tokens (94.3% lower; 17.6x difference).
GPT-6 Luna has 50K more context (1.05x larger).
GPT-6 Luna is $6.85 cheaper on the standard workload (95.1% 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-6 Luna has the lower input price; GPT-6 Luna has the lower output price; GPT-6 Luna offers the larger context window. For the 1M input plus 500K output sample, GPT-6 Luna is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $7.2 for GLM 5.3 Prime and $0.35 for GPT-6 Luna.
Choose GLM 5.3 Prime when its provider, model quality, latency, or availability is more important than the numeric price/context winner.
Choose GPT-6 Luna when you care most about lower input-token price, lower output-token price, and larger context window.
- On the standard 1M input plus 500K output workload, GPT-6 Luna is estimated at $0.35 vs $7.2 for GLM 5.3 Prime, saving $6.85 (95.1% lower).
- GPT-6 Luna is $6.85 cheaper on the standard workload (95.1% lower).
- GPT-6 Luna is $2.7 cheaper per 1M input tokens (96.4% lower; 28x difference).
- GPT-6 Luna is $8.3 cheaper per 1M output tokens (94.3% lower; 17.6x difference).
- GPT-6 Luna has 50K more context (1.05x larger).
| Feature | NewGLM 5.3 Prime (Z.ai) | NewGPT-6 Luna (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $2.8 | $0.1 |
| Completion Price per 1M tokens | $8.8 | $0.5 |
| Sample Workload Cost 1M input + 500K output | $7.2 | $0.35 |
| Context Window | 1M | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | GPT-6 Luna | On the standard 1M input plus 500K output workload, GPT-6 Luna is estimated at $0.35 vs $7.2 for GLM 5.3 Prime, saving $6.85 (95.1% lower). |
| High-volume input processing | GPT-6 Luna | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | GPT-6 Luna | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-6 Luna | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- GLM 5.2 (free) can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.
- GLM 4.5 Air (free) can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.
- GLM 4 32B can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.15.
- GLM 5.3 Flash (batch) can replace GLM 5.3 Prime when lower sample workload cost matters most: $0.16.
- Grok 4.20 Multi-Agent offers 2M context with $2.5 sample workload cost.
- Grok 4.20 offers 2M context with $2.5 sample workload cost.
- GLM 5.3 Flash offers 1.31M context with $0.4 sample workload cost.
- DeepSeek V4 Flash 0731 offers 1.31M context with $0.36 sample workload cost.
- MiMo-V2.6-Pro · Xiaomi · #1
- GLM 5.3 Flash · Z.ai · #2
- DeepSeek V4.1 Flash · DeepSeek · #3
- Hy4 preview · Tencent · #4
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