GPT-5.3 Codex Environmental Impact
Most capable agentic coding model — SoTA on SWE-Bench Pro
- Architecture
- Code-optimised Transformer with agentic reasoning
- Context
- 256,000 tokens
- Provider
- OpenAI
Energy per query
4.5 Wh
15x more than a Google search (0.3 Wh)
CO2 per query
2.0 g
US East (Virginia) grid (450 gCO₂/kWh)
Water per query
16 mL
~62 queries to fill 1 litre
Processing location
Azure / Multi-cloud
Provider
OpenAI
Category
Code Assistant
Grid carbon intensity
450 g CO2/kWh (25% renewable)
How does GPT-5.3 Codex compare?
Detailed Breakdown
Energy Consumption
GPT-5.3 Codex combines the Codex and GPT-5 stacks for state-of-the-art agentic coding. At ~4.5 Wh per step, it is 25% faster than GPT-5.2 Codex with improved interactive steering — users can redirect the agent while it works. The Spark variant runs at 1000+ tokens/sec on Cerebras hardware.
Power Source & Carbon
Runs on OpenAI's multi-cloud infrastructure. The Spark variant uses Cerebras wafer-scale chips for near-instant inference.
About GPT-5.3 Codex
GPT-5.3 Codex is a code assistant model from OpenAI, released in February 5, 2026. Most capable agentic coding model — SoTA on SWE-Bench Pro. Each query uses 4.5 Wh of energy and produces 2.0 g of CO₂. That's 15x the energy of a Google search — reflecting the computational demands of code assistant.
These figures are estimates derived from hardware specifications and API benchmarks — OpenAI has not published official energy data for GPT-5.3 Codex. Actual consumption may vary significantly depending on batching, quantisation, and infrastructure optimisations that we cannot observe from outside.
GPT-5.3 Codex in Context
The efficiency alternative
Devstral 2 performs the same type of task using just 0.60 Wh per query — 87% less energy than GPT-5.3 Codex. For a user sending 25 queries per day, switching would save 35.6 kWh per year.
Your yearly GPT-5.3 Codex footprint
At 25 queries per day, your annual GPT-5.3 Codex usage consumes 41.1 kWh — roughly what a fridge uses in a month. That produces 17.9 kg of CO₂.
OpenAI GPT Family
How energy efficiency has evolved across versions.
What does your GPT-5.3 Codex usage cost the planet?
Use our calculator to estimate your personal environmental footprint based on how often you use GPT-5.3 Codex.
Calculate My ComputeFrequently Asked Questions
How much energy does GPT-5.3 Codex use per query?
Each GPT-5.3 Codex query consumes approximately 4.5 Wh of energy. This is 15x more than a traditional Google search (~0.3 Wh).
What is GPT-5.3 Codex's carbon footprint?
Based on the carbon intensity of Azure / Multi-cloud, each query produces approximately 2.0 g of CO2. The grid in this region has a carbon intensity of 450 g CO2/kWh with 25% renewable energy.
How much water does GPT-5.3 Codex use?
Each query consumes approximately 16 mL of water, primarily used for cooling the data centers that process the request.
How does GPT-5.3 Codex compare to a Google search?
A GPT-5.3 Codex query uses 15x more than a Google search in terms of energy. A Google search uses approximately 0.3 Wh, while GPT-5.3 Codex uses 4.5 Wh.
Technical Details
Architecture
Code-optimised Transformer with agentic reasoning
Context window
256,000 tokens
Release date
2026-02-05
Open source
No
Training data cutoff
2026-01