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Claude 3.7 Sonnet 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 3.7 Sonnet specs · o3 specs
Verdict by category
  • Priceo3

    o3 is roughly 1.9× cheaper on output tokens ($8.00 vs $15.00 per 1M).

  • Context windowTie

    Both ship a 200K-token context window.

  • Benchmarkso3

    o3 leads in 1 of 1 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 95.0 vs 92.0.

  • ModalitiesTie

    Both handle text, vision.

  • OpennessTie

    Both are closed-weight, API-only.

On balance o3 edges ahead, winning 2 of 5 categories against Claude 3.7 Sonnet's 0. o3 is roughly 1.9× cheaper on output tokens ($8.00 vs $15.00 per 1M). Both ship a 200K-token context window.

o3 leads in 1 of 1 shared benchmarks; the biggest gap is on HumanEval (Python coding), where it scores 95.0 vs 92.0. 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.

o3 is the newer of the two, released 2 months after Claude 3.7 Sonnet, which usually means a more recent knowledge cutoff and updated safety post-training. Claude 3.7 Sonnet is usually picked for coding llm and creative writing 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 3.7 Sonneto3
ProviderAnthropicOpenAI
ReleasedFeb 2025Apr 2025
Modalitiestext, visiontext, vision
Context window200K tokens200K tokens
Max output,,
Input · 1M$3.00 / 1M tokens$2.00 / 1M tokens
Output · 1M$15.00 / 1M tokens$8.00 / 1M tokens
Knowledge cutoff2024-102024-06
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$31.50 vs $18.00
  • Heavy usage, 1M in / 500k out per day$315 vs $180
  • RAG workload, 5M in / 200k out per day$540 vs $348

Light usage, 100k in / 50k out per day: $31.50 vs $18.00 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $315 vs $180 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $540 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 3.7 Sonnet$1.05
  • 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 3.7 Sonneto3
  • HumanEval92.095.0
  • GPQA,87.7
  • SWE-bench Verified62.3
Pick Claude 3.7 Sonnet if

Claude 3.7 Sonnet fits when…

  • First Claude with extended thinking
  • Excellent writing and coding quality
  • Mature, widely-tested
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, 1.9× cheaper than Claude 3.7 Sonnet 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 3.7 Sonnet vs Claude Opus 4.7o3 vs Claude Opus 4.7

Frequently asked

  • Is Claude 3.7 Sonnet or o3 cheaper?
    o3 is cheaper at $8.00 / 1M tokens per million output tokens, vs $15.00 / 1M tokens for Claude 3.7 Sonnet.
  • Which has the larger context window?
    Both Claude 3.7 Sonnet and o3 ship a 200K-token context window.
  • Is Claude 3.7 Sonnet or o3 better for coding?
    Both Claude 3.7 Sonnet 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 3.7 Sonnet and o3 released?
    Claude 3.7 Sonnet was released by Anthropic on 2025-02-24. o3 was released by OpenAI on 2025-04-16.
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