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Claude Opus 4 vs o3-mini

A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.

Updated

Claude Opus 4 specs · o3-mini specs
Verdict by category
  • Priceo3-mini

    o3-mini is roughly 17.0× cheaper on output tokens ($4.40 vs $75.00 per 1M).

  • Context windowTie

    Both ship a 200K-token context window.

  • BenchmarksTie

    No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.

  • ModalitiesClaude Opus 4

    Claude Opus 4 supports 2 modalities (text, vision) vs 1 for o3-mini.

  • OpennessTie

    Both are closed-weight, API-only.

It's a genuine coin-flip between Claude Opus 4 and o3-mini: 1 category wins each, with the rest tied. o3-mini is roughly 17.0× cheaper on output tokens ($4.40 vs $75.00 per 1M). Both ship a 200K-token context window.

No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, Claude Opus 4 handles text, vision while o3-mini handles text, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.

Claude Opus 4 is the newer of the two, released 4 months after o3-mini, which usually means a more recent knowledge cutoff and updated safety post-training. Claude Opus 4 is usually picked for coding llm and coding agent workloads, while o3-mini sees more deployments in reasoning and math. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecClaude Opus 4o3-mini
ProviderAnthropicOpenAI
ReleasedMay 2025Jan 2025
Modalitiestext, visiontext
Context window200K tokens200K tokens
Max output,,
Input · 1M$15.00 / 1M tokens$1.10 / 1M tokens
Output · 1M$75.00 / 1M tokens$4.40 / 1M tokens
Knowledge cutoff2025-032023-10
Open weightsNoNo
API availableYesYes

Pricing at scale

What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.

  • Light usage, 100k in / 50k out per day$158 vs $9.90
  • Heavy usage, 1M in / 500k out per day$1,575 vs $99.00
  • RAG workload, 5M in / 200k out per day$2,700 vs $191

Light usage, 100k in / 50k out per day: $158 vs $9.90 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $1,575 vs $99.00 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $2,700 vs $191 per month, model B comes out ahead.

Price calculator

Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.

  • Claude Opus 4$5.25
  • o3-mini$0.330

Benchmarks compared

Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.

Claude Opus 4o3-mini
  • HumanEval95.0
  • GPQA,79.7
  • SWE-bench Verified72.5
Pick Claude Opus 4 if

Claude Opus 4 fits when…

  • Set the SWE-bench bar at launch
  • Excellent for writing and code
  • Strong long-context handling
  • Multimodal needs covering vision.
Pick o3-mini if

o3-mini fits when…

  • Reasoning at mid-tier cost
  • Fast for a thinking model
  • Cost-sensitive workloads, 17.0× cheaper than Claude Opus 4 on output tokens.
Don't want either?

Consider Claude Opus 4.7

Anthropic's mid-2026 flagship, ahead on SWE-bench, agent reliability, and writing quality.

See Claude Opus 4.7 specsClaude Opus 4 vs Claude Opus 4.7o3-mini vs Claude Opus 4.7

Frequently asked

  • Is Claude Opus 4 or o3-mini cheaper?
    o3-mini is cheaper at $4.40 / 1M tokens per million output tokens, vs $75.00 / 1M tokens for Claude Opus 4.
  • Which has the larger context window?
    Both Claude Opus 4 and o3-mini ship a 200K-token context window.
  • Is Claude Opus 4 or o3-mini better for coding?
    Both Claude Opus 4 and o3-mini are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.
  • Are either of these models open source?
    Neither model ships open weights, both are accessible only via their respective providers' APIs.
  • When were Claude Opus 4 and o3-mini released?
    Claude Opus 4 was released by Anthropic on 2025-05-22. o3-mini was released by OpenAI on 2025-01-31.
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