Compare / GPT-5.6 Sol vs o3-pro
GPT-5.6 Sol vs o3-pro
Which is cheaper, which is more capable, and which does better at each kind of work, from 4 results on 2 sources that measured both models.
Of the 4 results both models have, the better value on each. Results whose reported ranges overlap are too close to call.
Results as of 10 November 2026 (catalogue release 2026-11-10-8342a7178929).
GPT-5.6 Sol or o3-pro? The short answer
Pick GPT-5.6 Sol: it scores higher (Intelligence Index 47.0 against 21.9) and costs less.
- GPT-5.6 Sol is cheaper: $8.00 against $35.00 per million tokens, 4.4 times less.
- GPT-5.6 Sol scores higher on the Artificial Analysis Intelligence Index: 47.0 against 21.9.
- GPT-5.6 Sol is newer: released 9 Jul 2026, against 10 Jun 2025 for o3-pro.
- On third-party benchmarks, on the results both models have: GPT-5.6 Sol does better for reasoning and knowledge and sticking to the facts.
Head to head
Every fact side by side
| GPT-5.6 Sol | o3-pro | |
|---|---|---|
| Price per million tokens | $4.00 in · $20.00 out | $20.00 in · $80.00 out |
| Blended (3 in : 1 out) | $8.00 | $35.00 |
| Cheapest host, blended | $8.00 (Amazon Bedrock) | – |
| Cached input, per million | $0.40 cached input | – |
| Intelligence Index | 47.0 | 21.9 |
| Spring Prompt overall | – | – |
| Output speed, tokens a second | – | – |
| Context window | 1,050,000 tokens | 200,000 tokens |
| Released | 9 Jul 2026 (newer) | 10 Jun 2025 |
| Weights | Closed | Closed |
| Developer based in | the US | the US |
Prices are the developer's list price where we have read it, otherwise the typical host on OpenRouter; see every model's price. Intelligence and speed from Artificial Analysis.
Which is better for what
Each model's rank among the models on sale today, for each kind of work, from our own benchmarks and licensed sources. Further right is better; the better rank is in green.
Every shared result
Each model's best result on every measure both have, grouped by benchmark, with the setting that produced it. Under each measure, every model that benchmark has measured is a grey tick, best to the right, so you can see where the two sit in the field. The headline measures of each benchmark come first; the rest are under "Show all". Green marks the better value; where a source reports ranges that overlap, neither is marked.
| Measure | GPT-5.6 Sol | o3-pro |
|---|---|---|
| Artificial Analysis reported by Artificial Analysis · 2 results | ||
| Artificial Analysis Intelligence Indexindex score, higher is better 12 · 100 of 249 measured | 47.0max reasoning | 21.9 |
| GPQA Diamond% of questions, higher is better 5 · 85 of 232 measured | 94.1%max reasoning | 84.5% |
| Vectara Hallucination Leaderboard reported by Vectara Hallucination Leaderboard · 2 results | ||
| Hallucination rate · Vectara% of summaries, lower is better 83 · 102 of 104 measured | 12.4% | 23.3% |
| Answer rate · Vectara% of documents, higher is better 61 · 1 of 104 measured | 99.1% | 100.0% |
Quick answers
Is GPT-5.6 Sol better than o3-pro?
Pick GPT-5.6 Sol: it scores higher (Intelligence Index 47.0 against 21.9) and costs less.
Which is cheaper, GPT-5.6 Sol or o3-pro?
GPT-5.6 Sol is cheaper: $8.00 against $35.00 per million tokens, 4.4 times less.
Which is better for reasoning and knowledge, GPT-5.6 Sol or o3-pro?
GPT-5.6 Sol ranks 10 of 187 models on sale for hard questions across science, maths and general knowledge, against 90 for o3-pro.
Which is better for sticking to the facts, GPT-5.6 Sol or o3-pro?
GPT-5.6 Sol ranks 45 of 139 models on sale for summarising without inventing things, and factual answers, against 136 for o3-pro.
Which has the bigger context window, GPT-5.6 Sol or o3-pro?
GPT-5.6 Sol: 1,050,000 tokens, against 200,000 for o3-pro.
Run GPT-5.6 Sol and o3-pro on your own prompt.
Benchmarks aren't your task. Test both side by side on your prompt, with every answer checked against your rules and the cost of each one.