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Comparison · 2 models · Updated Nov 2, 2026

o3-deep-research vs GPT-5 Chat

GPT-5 Chat comes out ahead, 31 to 24 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    o3-deep-research

    Released Jun 26, 2025

    24/100
    • ECI—
    • Price$9.00 / $36.00
    • Context200K
  2. Our pick

    OpenAI

    GPT-5 Chat

    Released Aug 7, 2025

    31/100
    • ECI—
    • Price$1.25 / $10.00
    • Context400K
  3. Add a model

    Make it a three-way comparison.

01 — Verdict

GPT-5 Chat is our pick

GPT-5 Chat is the better all-round choice, scoring 31/100 against o3-deep-research (24). It leads on price and context window. o3-deep-research wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest priceGPT-5 ChatGPT-5 Chat $3.44 · o3-deep-research $15.75 per 1M tokens (3:1 blend)
  • Longest contextGPT-5 ChatGPT-5 Chat 400,000 · o3-deep-research 200,000 tokens
  • Widest inputsSame inputso3-deep-research: Text, Images · GPT-5 Chat: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeighto3-deep-researchGPT-5 Chat
Price50%023
Inputs & features30%6035
Context window20%3244
Overall100%24/10031/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

o3-deep-research vs GPT-5 Chat specifications side by side
Specificationo3-deep-researchOpenAIGPT-5 ChatOpenAI
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$9.00$1.25 (best)
Output$36.00$10.00 (best)
Cached input——
Blended (3:1)$15.75$3.44 (best)
Long-context rateSame rateSame rate
Price sourceMedian of 1 providersMedian of 5 providers
Limits
Context window200,000 tokens400,000 tokens (best)
Max output100,000 tokens128,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoNo
AudioNoNo
VideoNoNo
ReasoningYesYes
Tool callingYesNo
Structured outputNoNo
Availability
WeightsProprietaryProprietary
API model ID——
API providers15 (best)
ReleasedJun 26, 2025Aug 7, 2025
Knowledge cutoffMay 2024Sep 30, 2024
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • o3-deep-research$162.00
  • GPT-5 Chat$32.50
04 — Questions

Which should you choose?

Which is better: o3-deep-research or GPT-5 Chat?

GPT-5 Chat is the better all-round choice, scoring 31/100 against o3-deep-research (24). It leads on price and context window. o3-deep-research wins on inputs & features. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, o3-deep-research or GPT-5 Chat?

GPT-5 Chat is cheaper at $1.25 input / $10.00 output per million tokens (median across 5 API providers). o3-deep-research costs $9.00 input / $36.00 output per million tokens (median across 1 API provider). At a typical mix of three input tokens to one output token, that is $3.44 per million tokens for GPT-5 Chat versus $15.75 for o3-deep-research (4.6× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. o3-deep-research has not been scored yet and GPT-5 Chat has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for o3-deep-research and GPT-5 Chat yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Note that GPT-5 Chat does not support tool calling, which most coding agents need.

Which has the bigger context window?

GPT-5 Chat has the largest context window at 400,000 tokens, against 200,000 for o3-deep-research. Maximum output per response: o3-deep-research up to 100,000, GPT-5 Chat up to 128,000 tokens.

Which can read images, PDFs, audio or video?

o3-deep-research accepts text and images; GPT-5 Chat accepts text and images. They handle the same number of input types.

Are any of these open source?

No. o3-deep-research and GPT-5 Chat are proprietary and only available through APIs and apps.

Which is newer?

GPT-5 Chat is the newest, released Aug 7, 2025. o3-deep-research came out Jun 26, 2025. Knowledge cutoff: o3-deep-research May 2024, GPT-5 Chat Sep 30, 2024.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Nov 2, 2026.