Model comparison
GPT-5.5 Pro vs Mercury
GPT-5.5 Pro is the stronger model overall, scoring 64.3 to 37.3 on the Noometry Index.
Last verified . 0 shared benchmarks.
Summary
- The widest gap is in reasoning, where GPT-5.5 Pro leads 73.6 to 16.8.
Side by side
| GPT-5.5 Pro | Mercury | |
|---|---|---|
| Provider | OpenAI | Inception |
| Noometry Index | 64.3 | 37.3 |
| Released | 2026-04-23 | — |
| Weights | Proprietary | Proprietary |
| Context window | 1.05M | — |
| Max output | 128K | — |
| Input $ / M tokens | $30 | — |
| Output $ / M tokens | $180 | — |
| Results tracked | 14 | 9 |
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Category by category
Coding Not comparable
GPT-5.5 Pro: —, Mercury: 38.1 (#164)
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| LMArena Coding | — | 1323 |
Reasoning GPT-5.5 Pro leads
GPT-5.5 Pro: 73.6 (#7), Mercury: 16.8 (#288)
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| ARC-AGI-2 | 84.6% | — |
| SimpleBench | 76.9% | — |
| Kagi LLM Benchmark | — | 21.6% |
| ARC-AGI-1 | 96.5% | — |
| CritPt | 30.6% | — |
| Chess Puzzles | 64% | — |
| LMArena Hard Prompts | — | 1284 |
| DTBench | 96% | — |
| LMCA | 53.9% | — |
| Epoch Capabilities Index | 162.45 | — |
Math Not comparable
GPT-5.5 Pro: 83.8 (#8), Mercury: —
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| FrontierMath (Tiers 1-3) | 87.7% | — |
| FrontierMath Tier 4 | 78% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| FrontierMath (Feb 2025 set) | 52.4% | — |
| FrontierMath Tier 4 (v1) | 39.6% | — |
Knowledge Not comparable
GPT-5.5 Pro: 64.2 (#17), Mercury: —
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| GPQA Diamond | 93.9% | — |
Multilingual Not comparable
GPT-5.5 Pro: —, Mercury: 41.7 (#201)
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| LMArena Non-English | — | 1259 |
Instruction Following Not comparable
GPT-5.5 Pro: —, Mercury: 65.3 (#220)
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| LMArena Instruction Following | — | 1238 |
Long Context Not comparable
GPT-5.5 Pro: —, Mercury: 38.3 (#193)
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| LMArena Longer Query | — | 1264 |
Writing & Preference Not comparable
GPT-5.5 Pro: —, Mercury: 46.2 (#216)
| Benchmark | GPT-5.5 Pro | Mercury |
|---|---|---|
| LMArena Text | — | 1282 |
| LMArena Creative Writing | — | 1186 |
| LMArena Multi-Turn | — | 1283 |
Frequently asked questions
Is GPT-5.5 Pro better than Mercury?
GPT-5.5 Pro is the stronger model overall, scoring 64.3 to 37.3 on the Noometry Index.
How many benchmarks do GPT-5.5 Pro and Mercury share?
0 benchmarks have published results for both models. GPT-5.5 Pro has 14 scored results on Noometry and Mercury has 9.