GPT-5.6 Luna: cost, energy and CO₂ per token
What is the footprint of GPT-5.6 Luna? GPT-5.6 Luna emits about 308 g of CO₂e, uses 3.7 L of water and 706 Wh of electricity per million generated tokens. Per million input tokens: 51 g of CO₂e, 610 mL of water, 118 Wh. Public price: €5 per million generated tokens, €0.87 for input.
Factors tokenclimate-v5-2026-07, updated on , low confidence. Sources and equations in the methodology.
Key figures, per million tokens
| Energy | CO₂e | Water | Price | |
|---|---|---|---|---|
| Input tokens | 118 Wh | 51 g | 610 mL | €0.87 |
| Generated tokens | 706 Wh | 308 g | 3.7 L | €5 |
Of the 20 models in the TokenClimate registry, GPT-5.6 Luna ranks 7th for carbon intensity per million generated tokens, below the median (723 g). The gap with Mistral Small, the registry's most frugal, is still ×14.
One million generated tokens represents about 3 km in a petrol car.
Frequently asked questions
How much CO₂e for 1 million tokens with GPT-5.6 Luna?
About 308 g per million generated tokens and 51 g per million input tokens (factors tokenclimate-v5-2026-07 of the TokenClimate registry).
Where do these figures come from?
Factors published in TokenClimate's versioned registry, each with its citation on this page. The full equations and parameters are in the public methodology, at tokenclimate.com/en/methodology.
What is the confidence level?
Low confidence: extrapolation from a close model.
How can you measure your organisation's real usage?
The AI usage report computes twelve months of cost and CO₂e from your organisation's Anthropic admin key (the key is never stored), ready in about fifteen minutes: tokenclimate.com/bilan/en. Locally, the open source plugin claude-carbon measures a Claude Code session.
Sources and method
Energy per token
The per-token energy factor behind the figures above, published with its citation.
Infrastructure parameters
Datacenter parameters applied to this provider (the equations live in the methodology). (Jegham et al., arXiv:2505.09598 (v6))
| PUE | 1.12 |
| Grid carbon intensity (CIF) | 0.35 kgCO₂e/kWh |
| On-site water (WUE) | 0.3 L/kWh |
| Off-site water (EWIF) | 4.35 L/kWh |
| Amortised manufacturing (embodied) | 44 gCO₂e/kWh |
Price
Public provider prices.
Full equations and assumptions in the methodology.
Are you a developer? Measure your real Claude Code usage
curl -fsSL "https://tokenclimate.com/install.sh?ref=models" | bashThe command installs the team CLI (you need your organisation's invitation code). Solo, the open source local version claude-carbon installs with npx claude-carbon, no account needed. Or estimate a volume first with the calculator.