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Claude Opus 4 vs o3

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 specs
Verdict by category
  • Priceo3

    o3 is roughly 9.4× cheaper on output tokens ($8.00 vs $75.00 per 1M).

  • Context windowTie

    Both ship a 200K-token context window.

  • BenchmarksTie

    Across 1 shared benchmarks the two models split wins evenly. Look at task-specific scores rather than the average.

  • ModalitiesTie

    Both handle text, vision.

  • OpennessTie

    Both are closed-weight, API-only.

On balance o3 edges ahead, winning 1 of 5 categories against Claude Opus 4's 0. o3 is roughly 9.4× cheaper on output tokens ($8.00 vs $75.00 per 1M). Both ship a 200K-token context window.

Across 1 shared benchmarks the two models split wins evenly. Look at task-specific scores rather than the average. Both target the same set of modalities (text, vision), so the deciding factors are price, context, and raw quality. Both are closed-weight, API-only.

Claude Opus 4 is the newer of the two, released 1 months after o3, 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 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
ProviderAnthropicOpenAI
ReleasedMay 2025Apr 2025
Modalitiestext, visiontext, vision
Context window200K tokens200K tokens
Max output,,
Input · 1M$15.00 / 1M tokens$2.00 / 1M tokens
Output · 1M$75.00 / 1M tokens$8.00 / 1M tokens
Knowledge cutoff2025-032024-06
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 $18.00
  • Heavy usage, 1M in / 500k out per day$1,575 vs $180
  • RAG workload, 5M in / 200k out per day$2,700 vs $348

Light usage, 100k in / 50k out per day: $158 vs $18.00 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $1,575 vs $180 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $2,700 vs $348 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$0.600

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
  • HumanEval95.095.0
  • GPQA,87.7
  • 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
Pick o3 if

o3 fits when…

  • Industry-leading reasoning depth at launch
  • Strong on math, science, and abstract puzzles
  • Tool-use during reasoning loops
  • Cost-sensitive workloads, 9.4× 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 vs Claude Opus 4.7

Frequently asked

  • Is Claude Opus 4 or o3 cheaper?
    o3 is cheaper at $8.00 / 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 ship a 200K-token context window.
  • Is Claude Opus 4 or o3 better for coding?
    Both Claude Opus 4 and o3 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 released?
    Claude Opus 4 was released by Anthropic on 2025-05-22. o3 was released by OpenAI on 2025-04-16.
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