Mercury 3 is $0.27 cheaper per 1M input tokens (73% lower; 3.7x difference).
API cost decision in 10 seconds
NewMercury 3 vs GLM 5.3 FlashX
Pick Mercury 3 for lower cost; pick GLM 5.3 FlashX 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 Mercury 3 for lower cost; pick GLM 5.3 FlashX only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Mercury 3 is estimated at $0.28 vs $0.99 for GLM 5.3 FlashX, saving $0.72 (72.4% lower).
Cost-first pickMercury 3
Context-first pickGLM 5.3 FlashX
Sample savings$0.7272.4%
10x traffic gap$7.2
GLM 5.3 FlashX has more context, but Mercury 3 saves $0.72 on the standard workload. At 10x that traffic, the same price gap is about $7.2. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Mercury 3 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Mercury 3 | GLM 5.3 FlashX |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Mercury 3 | $0.68 | $2.48 |
| Balanced workload | 1M input + 1M output | Mercury 3 | $0.45 | $1.62 |
| Output-heavy chatbot | 1M input + 5M output | Mercury 3 | $1.85 | $6.62 |
Mercury 3 is $0.9 cheaper per 1M output tokens (72% lower; 3.57x difference).
GLM 5.3 FlashX has 48.58K more context (1.05x larger).
Mercury 3 is $0.72 cheaper on the standard workload (72.4% 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
Mercury 3 has the lower input price; Mercury 3 has the lower output price; GLM 5.3 FlashX offers the larger context window. For the 1M input plus 500K output sample, Mercury 3 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.28 for Mercury 3 and $0.99 for GLM 5.3 FlashX.
Choose Mercury 3 when you care most about lower input-token price, and lower output-token price.
Choose GLM 5.3 FlashX when you care most about larger context window.
- On the standard 1M input plus 500K output workload, Mercury 3 is estimated at $0.28 vs $0.99 for GLM 5.3 FlashX, saving $0.72 (72.4% lower).
- Mercury 3 is $0.72 cheaper on the standard workload (72.4% lower).
- Mercury 3 is $0.27 cheaper per 1M input tokens (73% lower; 3.7x difference).
- Mercury 3 is $0.9 cheaper per 1M output tokens (72% lower; 3.57x difference).
- GLM 5.3 FlashX has 48.58K more context (1.05x larger).
| Feature | NewMercury 3 (Inception) | GLM 5.3 FlashX (Z.ai) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.1 | $0.37 |
| Completion Price per 1M tokens | $0.35 | $1.25 |
| Sample Workload Cost 1M input + 500K output | $0.28 | $0.99 |
| Context Window | 1M | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Mercury 3 | On the standard 1M input plus 500K output workload, Mercury 3 is estimated at $0.28 vs $0.99 for GLM 5.3 FlashX, saving $0.72 (72.4% lower). |
| High-volume input processing | Mercury 3 | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Mercury 3 | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GLM 5.3 FlashX | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Mercury 2.5 can replace Mercury 3 when lower sample workload cost matters most: $0.11.
- 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 5.3 Flash can replace GLM 5.3 FlashX when lower sample workload cost matters most: $0.13.
- Llama 4 Scout offers 1.31M context with $0.25 sample workload cost.
- MiMo-V2.6-Flash offers 1.05M context with $0.28 sample workload cost.
- GPT-6 Luna offers 1.05M context with $0.35 sample workload cost.
- GPT-6 Luna Pro offers 1.05M context with $0.35 sample workload cost.
- DeepSeek V4.1 Flash · DeepSeek · #1
- GLM 5.3 Flash · Z.ai · #2
- Step 5 Preview · StepFun · #3
- MiMo-V2.6-Flash · Xiaomi · #4
Cheaper alternatives
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Open Z.ai modelsMercury 3 is a diffusion-based language model from Inception, and the lab's most capable model to date. It is suited for agentic workflows and real-time applications where latency compounds, such...
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