OpenAI

GPT-5.3 Chat (latest) — Benchmark Scores, Pricing & Performance Analysis

Input Cost
$1.8/1M
Output Cost
$14.0/1M
Context Window
128K
Max Output
16K
Knowledge Cutoff
Aug 2025
Accepts
text, image

GPT-5.3 Chat (latest) is an AI model by OpenAI. View detailed benchmark scores, pricing data, and performance metrics on Serenities AI Models.

Specifications last checked against the provider on . Benchmark scores carry their own source, linked beside each number.

Reasoning Benchmarks

GPQA Diamond
80.5%60th of 140

Graduate-level science Q&A by domain experts

Papers
τ²-Bench Airline
46.0%77th of 93

Multi-turn service agent making tool calls under strict policy constraints

OpenRouter (measured)

Cost Benchmarks

Input Cost
$1.8329th of 413

Cost per 1M input tokens

OpenRouter API
Output Cost
$14.0364th of 413

Cost per 1M output tokens

OpenRouter API

Context Benchmarks

Context Length
128K267th of 451

Maximum context window size

OpenRouter API

Available from 6 providers

The same model costs different amounts depending on who serves it. You can bring your own key for 1 of these — connect it here.

ProviderInput / 1MOutput / 1MCached inContextYour key
302.AI$1.75$14128K
Abacus$1.75$14400K
Merge Gateway$1.75$14$0.175128K
OpenAI$1.75$14$0.175128KSupported
Opper$1.75$14$0.175128K
ZenMux$1.75$14128K

GPT-5.3 Chat (latest) — Benchmark Scores Overview

Scores normalized to percentage scale for visual comparison. ELO scores mapped to 0-100 range (1100-1500).

GPT-5.3 Chat (latest) — Frequently Asked Questions

How much does GPT-5.3 Chat (latest) cost?

GPT-5.3 Chat (latest) costs $1.8 per 1M input tokens and $14.0 per 1M output tokens. This is mid-range pricing for its capability level.

What is the context window of GPT-5.3 Chat (latest)?

GPT-5.3 Chat (latest) has a context window of 128K tokens. This determines how much text, conversation history, and code the model can process in a single request.

Who created GPT-5.3 Chat (latest)?

GPT-5.3 Chat (latest) was created by OpenAI. It is classified as a mid model in our catalogue.

Is GPT-5.3 Chat (latest) open source?

No, GPT-5.3 Chat (latest) is a proprietary model. It is available through OpenAI's API and compatible providers.