GLM 4.5 Air (free) is free for input tokens while DeepSeek V4 Flash costs $0.1 per 1M tokens.
API cost decision in 10 seconds
🔥DeepSeek V4 Flash vs GLM 4.5 Air (free)
Pick GLM 4.5 Air (free) for lower cost; pick DeepSeek V4 Flash 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 4.5 Air (free) for lower cost; pick DeepSeek V4 Flash only if the larger context window matters more.
On the standard 1M input plus 500K output workload, GLM 4.5 Air (free) is estimated at $0 vs $0.2 for DeepSeek V4 Flash, saving $0.2 (100% lower).
Cost-first pickGLM 4.5 Air (free)
Context-first pickDeepSeek V4 Flash
Sample savings$0.2100%
10x traffic gap$2
DeepSeek V4 Flash has more context, but GLM 4.5 Air (free) saves $0.2 on the standard workload. At 10x that traffic, the same price gap is about $2. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
GLM 4.5 Air (free) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | DeepSeek V4 Flash | GLM 4.5 Air (free) |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | GLM 4.5 Air (free) | $0.6 | $0 |
| Balanced workload | 1M input + 1M output | GLM 4.5 Air (free) | $0.3 | $0 |
| Output-heavy chatbot | 1M input + 5M output | GLM 4.5 Air (free) | $1.1 | $0 |
GLM 4.5 Air (free) is free for output tokens while DeepSeek V4 Flash costs $0.2 per 1M tokens.
DeepSeek V4 Flash has 917.5K more context (8x larger).
GLM 4.5 Air (free) is free for the standard workload while the other model is estimated at $0.2.
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 4.5 Air (free) has the lower input price; GLM 4.5 Air (free) has the lower output price; DeepSeek V4 Flash offers the larger context window. For the 1M input plus 500K output sample, GLM 4.5 Air (free) is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.2 for DeepSeek V4 Flash and $0 for GLM 4.5 Air (free).
Choose DeepSeek V4 Flash when you care most about larger context window.
Choose GLM 4.5 Air (free) when you care most about lower input-token price, and lower output-token price.
- On the standard 1M input plus 500K output workload, GLM 4.5 Air (free) is estimated at $0 vs $0.2 for DeepSeek V4 Flash, saving $0.2 (100% lower).
- GLM 4.5 Air (free) is free for the standard workload while the other model is estimated at $0.2.
- GLM 4.5 Air (free) is free for input tokens while DeepSeek V4 Flash costs $0.1 per 1M tokens.
- GLM 4.5 Air (free) is free for output tokens while DeepSeek V4 Flash costs $0.2 per 1M tokens.
- DeepSeek V4 Flash has 917.5K more context (8x larger).
| Feature | 🔥DeepSeek V4 Flash (DeepSeek) | GLM 4.5 Air (free) (Z.ai) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.1 | $0 |
| Completion Price per 1M tokens | $0.2 | $0 |
| Sample Workload Cost 1M input + 500K output | $0.2 | $0 |
| Context Window | 1.05M | 131.07K |
| Release Date | ||
| Popularity | #1 | #41 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | GLM 4.5 Air (free) | On the standard 1M input plus 500K output workload, GLM 4.5 Air (free) is estimated at $0 vs $0.2 for DeepSeek V4 Flash, saving $0.2 (100% lower). |
| High-volume input processing | GLM 4.5 Air (free) | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | GLM 4.5 Air (free) | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | DeepSeek V4 Flash | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- DeepSeek V4 Flash (free) can replace DeepSeek V4 Flash when lower sample workload cost matters most: $0.
- Llama 4 Scout offers 10M context with $0.23 sample workload cost.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- Hy3 preview · Tencent · #2
- Claude Opus 4.7 · Anthropic · #3
- Claude Sonnet 4.6 · Anthropic · #4
- Owl Alpha · OpenRouter · #5
Cheaper alternatives
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