token.app › Compare › GPT-5.6 Luna Pro vs Mercury 3
GPT-5.6 Luna Pro vs Mercury 3
Mercury 3 is 2.8× cheaper per token on a blended 3:1 basis. GPT-5.6 Luna Pro accepts the larger context window (1.1M).
Head to head
Blended price uses a 3:1 input:output mix
| GPT-5.6 Luna Pro | Mercury 3 | |
|---|---|---|
| Provider | OpenAI | Inception |
| Input $/1M | $0.200 | $0.100 |
| Output $/1M | $1.20 | $0.350 |
| Blended $/1M | $0.450 | $0.163 |
| Context window | 1.1M | 1M |
| Max output | 128K | 131K |
| Released | Jul 2026 | Oct 2026 |
| Licence | Proprietary | Proprietary |
Choose GPT-5.6 Luna Pro if…
- Larger context window (1.1M)
Choose Mercury 3 if…
- Costs less per token — $0.163 vs $0.450 blended
- Newer model (released Oct 2026)
FAQ
Which is better, GPT-5.6 Luna Pro or Mercury 3?
We do not hold independently-run benchmark scores covering both GPT-5.6 Luna Pro and Mercury 3, so we make no quality claim. Their pricing and specifications are compared on this page.
Is GPT-5.6 Luna Pro cheaper than Mercury 3?
Mercury 3 is cheaper: $0.163 versus $0.450 per million tokens blended at 3:1 input:output. Input alone: $0.200 vs $0.100. Output alone: $1.20 vs $0.350.
What context windows do GPT-5.6 Luna Pro and Mercury 3 have?
GPT-5.6 Luna Pro: 1,050,000 tokens. Mercury 3: 1,000,000 tokens.
Who makes GPT-5.6 Luna Pro and Mercury 3?
GPT-5.6 Luna Pro is made by OpenAI. Mercury 3 is made by Inception.
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