GLM 5.3 FlashX is $1.63 cheaper per 1M input tokens (81.5% lower; 5.41x difference).
API cost decision in 10 seconds
NewGLM 5.3 FlashX vs GPT-5.6 Terra
Pick GLM 5.3 FlashX for lower cost; pick GPT-5.6 Terra only if the larger context window matters more.
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Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick GLM 5.3 FlashX for lower cost; pick GPT-5.6 Terra only if the larger context window matters more.
On the standard 1M input plus 500K output workload, GLM 5.3 FlashX is estimated at $0.99 vs $8 for GPT-5.6 Terra, saving $7 (87.6% lower).
Cost-first pickGLM 5.3 FlashX
Context-first pickGPT-5.6 Terra
Sample savings$787.6%
10x traffic gap$70.05
GPT-5.6 Terra has more context, but GLM 5.3 FlashX saves $7 on the standard workload. At 10x that traffic, the same price gap is about $70.05. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
GLM 5.3 FlashX stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | GLM 5.3 FlashX | GPT-5.6 Terra |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | GLM 5.3 FlashX | $2.48 | $16 |
| Balanced workload | 1M input + 1M output | GLM 5.3 FlashX | $1.62 | $14 |
| Output-heavy chatbot | 1M input + 5M output | GLM 5.3 FlashX | $6.62 | $62 |
GLM 5.3 FlashX is $10.75 cheaper per 1M output tokens (89.6% lower; 9.6x difference).
GPT-5.6 Terra has 1.42K more context (1x larger).
GLM 5.3 FlashX is $7 cheaper on the standard workload (87.6% 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
GLM 5.3 FlashX has the lower input price; GLM 5.3 FlashX has the lower output price; GPT-5.6 Terra offers the larger context window. For the 1M input plus 500K output sample, GLM 5.3 FlashX is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.99 for GLM 5.3 FlashX and $8 for GPT-5.6 Terra.
Choose GLM 5.3 FlashX when you care most about lower input-token price, and lower output-token price.
Choose GPT-5.6 Terra when you care most about larger context window.
- On the standard 1M input plus 500K output workload, GLM 5.3 FlashX is estimated at $0.99 vs $8 for GPT-5.6 Terra, saving $7 (87.6% lower).
- GLM 5.3 FlashX is $7 cheaper on the standard workload (87.6% lower).
- GLM 5.3 FlashX is $1.63 cheaper per 1M input tokens (81.5% lower; 5.41x difference).
- GLM 5.3 FlashX is $10.75 cheaper per 1M output tokens (89.6% lower; 9.6x difference).
- GPT-5.6 Terra has 1.42K more context (1x larger).
| Feature | NewGLM 5.3 FlashX (Z.ai) | GPT-5.6 Terra (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.37 | $2 |
| Completion Price per 1M tokens | $1.25 | $12 |
| Sample Workload Cost 1M input + 500K output | $0.99 | $8 |
| Context Window | 1.05M | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | GLM 5.3 FlashX | On the standard 1M input plus 500K output workload, GLM 5.3 FlashX is estimated at $0.99 vs $8 for GPT-5.6 Terra, saving $7 (87.6% lower). |
| High-volume input processing | GLM 5.3 FlashX | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | GLM 5.3 FlashX | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-5.6 Terra | 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 FlashX when lower sample workload cost matters most: $0.
- GLM 4.5 Air (free) can replace GLM 5.3 FlashX when lower sample workload cost matters most: $0.
- GLM 4 32B can replace GLM 5.3 FlashX when lower sample workload cost matters most: $0.15.
- GLM Flash Latest can replace GLM 5.3 FlashX when lower sample workload cost matters most: $0.2.
- 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 $0.24 sample workload cost.
- DeepSeek V4 Flash 0731 offers 1.31M context with $0.08 sample workload cost.
- Qwen3.8 Max (0902) · Qwen · #1
- GPT-5.6 Luna · OpenAI · #2
- DeepSeek V4.1 Flash · DeepSeek · #3
- Hy4 preview · Tencent · #4
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