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Comparison · 2 models · Updated Oct 4, 2026

GPT-5.3 Chat vs GPT-5.2

GPT-5.2 comes out ahead, 39 to 32 on our weighted score.

  1. OpenAI

    GPT-5.3 Chat

    Released Mar 3, 2026Deprecated

    32/100
    • ECI—
    • Price$1.75 / $14.00
    • Context128K
    Full specs Remove GPT-5.3 Chat
  2. Our pick

    OpenAI

    GPT-5.2

    Released Dec 11, 2025

    39/100
    • ECI153.5
    • Price$1.75 / $14.00
    • Context400K
    Full specs Remove GPT-5.2

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

GPT-5.2 is our pick

GPT-5.2 is the better all-round choice, scoring 39/100 against GPT-5.3 Chat (32). It leads on inputs & features and context window. 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 priceSame priceGPT-5.3 Chat $4.81 · GPT-5.2 $4.81 per 1M tokens (3:1 blend)
  • Longest contextGPT-5.2GPT-5.2 400,000 · GPT-5.3 Chat 128,000 tokens
  • Widest inputsSame inputsGPT-5.3 Chat: Text, Images · GPT-5.2: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-5.3 ChatGPT-5.2
Price50%1818
Inputs & features30%6070
Context window20%2444
Overall100%32/10039/100

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.

GPT-5.3 Chat vs GPT-5.2 specifications side by side
SpecificationGPT-5.3 ChatOpenAIGPT-5.2OpenAI
Capability
Capabilities Index (ECI)—153.5
ECI rank—#38 of 148
GPQA DiamondGraduate-level science questions—91.4%
FrontierMath Tiers 1–3Research-level mathematics—67.4%
OTIS Mock AIME 2024–2025Competition mathematics—96.1%
SWE-bench VerifiedFixing real GitHub issues—73.8%
SimpleQA VerifiedShort factual questions—37.1%
Price per million tokens
Input$1.75$1.75
Output$14.00$14.00
Cached input$0.175$0.175
Blended (3:1)$4.81$4.81
Long-context rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial OpenAI API
Limits
Context window128,000 tokens400,000 tokens (best)
Max output16,384 tokens128,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoNo
AudioNoNo
VideoNoNo
ReasoningNoYeslow · medium · high · xhigh
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgpt-5.3-chat-latestgpt-5.2
API providers421 (best)
ReleasedMar 3, 2026Dec 11, 2025
Knowledge cutoffAug 31, 2025Aug 31, 2025
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.

  • GPT-5.3 Chat$45.50
  • GPT-5.2$45.50
04 — Questions

Which should you choose?

Which is better: GPT-5.3 Chat or GPT-5.2?

GPT-5.2 is the better all-round choice, scoring 39/100 against GPT-5.3 Chat (32). It leads on inputs & features and context window. 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, GPT-5.3 Chat or GPT-5.2?

GPT-5.3 Chat and GPT-5.2 cost the same: $1.75 input / $14.00 output per million tokens.

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. GPT-5.3 Chat has not been scored yet and GPT-5.2 has an ECI of 153.5.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.3 Chat yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

GPT-5.2 has the largest context window at 400,000 tokens, against 128,000 for GPT-5.3 Chat. Maximum output per response: GPT-5.3 Chat up to 16,384, GPT-5.2 up to 128,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5.3 Chat accepts text and images; GPT-5.2 accepts text and images. They handle the same number of input types.

Are any of these open source?

No. GPT-5.3 Chat and GPT-5.2 are proprietary and only available through APIs and apps.

Which is newer?

GPT-5.3 Chat is the newest, released Mar 3, 2026. GPT-5.2 came out Dec 11, 2025. Knowledge cutoff: GPT-5.3 Chat Aug 31, 2025, GPT-5.2 Aug 31, 2025.

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 Oct 4, 2026.

05 — Keep comparing

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