GPT-5.4 nano vs o3
| Spec | GPT-5.4 nano | o3 |
|---|---|---|
| Respan Index | 23.8 (#98) | 26.1 (#97) |
| Blended price per 1M | $0.463 | $3.5 |
| Context window | 400K | 200K |
| Input / output per 1M | $0.2 / $1.25 | $2 / $8 |
| Max output | 128K | 100K |
| Input | text, vision | text, vision |
| Released | 2026-03-17 | 2025-04-16 |
Respan Index by category
Each category is scored 0 to 100, and how far ahead the winner is. Leads under a point are close to even.
| Category | GPT-5.4 nano | o3 |
|---|---|---|
| Coding | 9.2 GPT-5.4 nano | 8.0 o3 |
| Agents | 21.5 GPT-5.4 nano | 8.6 o3 |
| Reasoning | 32.0 GPT-5.4 nano | 38.9 o3 |
| Knowledge & language | 13.2 GPT-5.4 nano | 49.3 o3 |
| Human preference | 45.2 GPT-5.4 nano | 48.6 o3 |
Benchmarks both report
o3 leads on 6 of the 10 benchmarks both report. Higher is better. Each score links to where it was published.
| Benchmark | GPT-5.4 nano | o3 |
|---|---|---|
| Chess Puzzles (Epoch AI) | 45% | 37% |
| LMArena Elo | 1401 | 1432 |
| LMArena Vision (LMArena) | 1199 | 1216 |
| FrontierMath Tiers 1-3 v2 (Epoch AI) | 44.9% | 33.3% |
| GPQA Diamond | 82.8% | 81.8% |
| Mystery Game Puzzles (Epoch AI) | 9% | 29% |
| OTIS Mock AIME 2024-2025 (Epoch AI) | 87.8% | 84.4% |
| SAGE (Vals AI) | 38.1% | 41.8% |
| SimpleQA Verified | 11.7% | 49.4% |
| WeirdML (Håvard Tveit Ihle) | 49.2% | 52.4% |
FAQ
Is GPT-5.4 nano better than o3?
o3 scores 26.1 on the Respan Index (#97), ahead of GPT-5.4 nano at 23.8 (#98). o3 leads on 6 of the 10 benchmarks both report.
Which is cheaper, GPT-5.4 nano or o3?
GPT-5.4 nano lists at $0.2 input and $1.25 output per 1M tokens; o3 at $2 and $8. GPT-5.4 nano is 7.6x cheaper per token at list price.
Which has the larger context window?
GPT-5.4 nano accepts 400K tokens and o3 200K tokens.