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Claude 3.5 Sonnet 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 3.5 Sonnet specs · o3-mini specs
Verdict by category
  • Priceo3-mini

    o3-mini is roughly 3.4× cheaper on output tokens ($4.40 vs $15.00 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 3.5 Sonnet

    Claude 3.5 Sonnet 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 3.5 Sonnet and o3-mini: 1 category wins each, with the rest tied. o3-mini is roughly 3.4× cheaper on output tokens ($4.40 vs $15.00 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 3.5 Sonnet 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.

o3-mini is the newer of the two, released 3 months after Claude 3.5 Sonnet, which usually means a more recent knowledge cutoff and updated safety post-training. Claude 3.5 Sonnet is usually picked for coding llm and code review 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 3.5 Sonneto3-mini
ProviderAnthropicOpenAI
ReleasedOct 2024Jan 2025
Modalitiestext, visiontext
Context window200K tokens200K tokens
Max output,,
Input · 1M$3.00 / 1M tokens$1.10 / 1M tokens
Output · 1M$15.00 / 1M tokens$4.40 / 1M tokens
Knowledge cutoff,2023-10
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$31.50 vs $9.90
  • Heavy usage, 1M in / 500k out per day$315 vs $99.00
  • RAG workload, 5M in / 200k out per day$540 vs $191

Light usage, 100k in / 50k out per day: $31.50 vs $9.90 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $315 vs $99.00 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $540 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 3.5 Sonnet$1.05
  • 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 3.5 Sonneto3-mini
  • HumanEval92.0
  • GPQA,79.7
Pick Claude 3.5 Sonnet if

Claude 3.5 Sonnet fits when…

  • Mature and battle-tested
  • Strong code
  • 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, 3.4× cheaper than Claude 3.5 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 3.5 Sonnet vs Claude Opus 4.7o3-mini vs Claude Opus 4.7

Frequently asked

  • Is Claude 3.5 Sonnet or o3-mini cheaper?
    o3-mini is cheaper at $4.40 / 1M tokens per million output tokens, vs $15.00 / 1M tokens for Claude 3.5 Sonnet.
  • Which has the larger context window?
    Both Claude 3.5 Sonnet and o3-mini ship a 200K-token context window.
  • Is Claude 3.5 Sonnet or o3-mini better for coding?
    Both Claude 3.5 Sonnet 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 3.5 Sonnet and o3-mini released?
    Claude 3.5 Sonnet was released by Anthropic on 2024-10-22. o3-mini was released by OpenAI on 2025-01-31.
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