Compare / Claude Opus 5.5 vs o3 Mini
Claude Opus 5.5 vs o3 Mini
Which is cheaper, which is more capable, and which does better at each kind of work, from 9 results on 3 sources that measured both models.
Claude Opus 5.5 or o3 Mini? The short answer
- o3 Mini is cheaper: $1.93 against $8.00 per million tokens, 4.2 times less.
- Claude Opus 5.5 scores higher on the Artificial Analysis Intelligence Index: 57.6 against 12.5.
- On our business benchmarks, Claude Opus 5.5 ranks higher for reasoning and knowledge, writing and sticking to the facts.
At a glance
| Claude Opus 5.5 | o3 Mini | |
|---|---|---|
| Price per million tokens | $4.00 in · $20.00 out | $1.10 in · $4.40 out |
| Blended (3 in : 1 out) | $8.00 | $1.93 |
| Cheapest host, blended | $8.00 (Amazon Bedrock) | – |
| Intelligence Index | 57.6 | 12.5 |
| Spring Prompt overall | 82 | – |
| Output speed, tokens a second | 97 | – |
| Context window | 1,000,000 tokens | 200,000 tokens |
| 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 models available today, for each kind of work, from our own benchmarks and licensed sources. The better rank is in green.
| Use case | Claude Opus 5.5 | o3 Mini |
|---|---|---|
| Product listingsTurning a sparse product feed and photos into listings that can go live | 6 of 19 | not measured |
| Decks from an analysisTurning a finished analysis into a deck you could present as it is | 5 of 18 | not measured |
| Marketing planningPlanning a year of ad spend without overspending | 5 of 18 | not measured |
| Agents and tool useMulti-step tasks with tools: support desks, coding agents, function calls | 2 of 161 | not measured |
| Professional workReal tasks from banking, consulting and law, business documents and freelance projects | 3 of 51 | not measured |
| Reasoning and knowledgeHard questions across science, maths and general knowledge | 1 of 195 | 129 of 195 |
| WritingWhat people prefer in blind comparisons, and judged writing quality | 4 of 187 | 140 of 187 |
| Sticking to the factsSummarising without inventing things, and factual answers | 6 of 153 | 140 of 153 |
| Speed under pressureGood decisions against a real clock (fast chess) | 22 of 22 | not measured |
Every shared result
| Benchmark | Metric | Claude Opus 5.5 | o3 Mini |
|---|---|---|---|
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,499 | 1,328 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,521 | 1,301 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,556 | 1,366 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,516 | 1,344 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,509 | 1,348 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,520 | 1,325 |
| Artificial Analysisreported | Artificial Analysis Intelligence Indexindex score | 57.6 | 12.5 |
| Artificial Analysisreported | Humanity's Last Exam% of questions | 61.4% | 7.9% |
| SimpleQA Verified (Epoch AI)reported | Correct answers% of questions | 72.2% | 15.3% |
Bold green marks the better value on that metric. Where a source reports ranges that overlap, the difference may not be meaningful; see the benchmark page for ranges.
Quick answers
Is Claude Opus 5.5 better than o3 Mini?
It depends on the task. Among models available today, on our benchmarks and licensed sources, Claude Opus 5.5 ranks higher for reasoning and knowledge, writing and sticking to the facts.
Which is cheaper, Claude Opus 5.5 or o3 Mini?
o3 Mini costs $1.93 per million tokens (three input to one output), against $8.00 for Claude Opus 5.5.
Run Claude Opus 5.5 and o3 Mini on your own prompt
Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.