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o4 vs Sonar Pro

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

Updated

o4 specs · Sonar Pro specs
Verdict by category
  • PriceSonar Pro

    Sonar Pro publishes pricing ($15.00 / 1M output tokens) while o4 does not.

  • 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.

  • Modalitieso4

    o4 supports 2 modalities (text, vision) vs 1 for Sonar Pro.

  • OpennessTie

    Both are closed-weight, API-only.

It's a genuine coin-flip between o4 and Sonar Pro: 1 category wins each, with the rest tied. Sonar Pro publishes pricing ($15.00 / 1M output tokens) while o4 does not. 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, o4 handles text, vision while Sonar Pro handles text, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.

o4 is the newer of the two, released 11 months after Sonar Pro, which usually means a more recent knowledge cutoff and updated safety post-training. o4 is usually picked for reasoning and math workloads, while Sonar Pro sees more deployments in research agent and rag. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

Speco4Sonar Pro
ProviderOpenAIPerplexity
ReleasedDec 2025Jan 2025
Modalitiestext, visiontext
Context window200K tokens200K tokens
Max output,,
Input · 1MPricing not published$3.00 / 1M tokens
Output · 1MPricing not published$15.00 / 1M tokens
Knowledge cutoff,,
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, vs $31.50
  • Heavy usage, 1M in / 500k out per day, vs $315
  • RAG workload, 5M in / 200k out per day, vs $540

Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).

Price calculator

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

  • o4Pricing unavailable
  • Sonar Pro$1.05

Benchmarks compared

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

Benchmark scores not yet available. We only publish numbers we can source from official model cards or independent leaderboards, see methodology.
Pick o4 if

o4 fits when…

  • Exceptional performance on hard math and reasoning benchmarks
  • Good at multi-step planning and verification
  • Strong scientific reasoning
  • Multimodal needs covering vision.
Pick Sonar Pro if

Sonar Pro fits when…

  • Multi-step web search
  • Deep research output
  • Citations
Don't want either?

Consider GPT-5.5

OpenAI's mid-cycle GPT-5 refresh, improved reasoning, tool use, and multimodal grounding over the 2025 launch.

See GPT-5.5 specso4 vs GPT-5.5Sonar Pro vs GPT-5.5

Frequently asked

  • Is o4 or Sonar Pro cheaper?
    Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.
  • Which has the larger context window?
    Both o4 and Sonar Pro ship a 200K-token context window.
  • Is o4 or Sonar Pro better for coding?
    Both o4 and Sonar Pro 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 o4 and Sonar Pro released?
    o4 was released by OpenAI on 2025-12-15. Sonar Pro was released by Perplexity on 2025-01-21.
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