AI model comparison

Claude Sonnet 4.6 vs GPT-5.2-Codex

Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.

Sonnet 4.6 is Anthropic's most capable Sonnet-class model yet, with frontier performance across coding, agents, and professional work.

Input / 1M
$3
Output / 1M
$15
Context
1M

GPT-5.2-Codex is an upgraded version of GPT-5.1-Codex optimized for software engineering and coding workflows.

Input / 1M
$1.75
Output / 1M
$14
Context
400K

At a glance

Quick verdict

How the two models stack up on the things people ask about most.

Lower price

openai logo

GPT-5.2-Codex

1.3x cheaper for a typical chat

Higher intelligence score

anthropic logo

Claude Sonnet 4.6

30.1 vs 28.5 on Artificial Analysis

Larger context window

anthropic logo

Claude Sonnet 4.6

1M vs 400K tokens

Newer release

anthropic logo

Claude Sonnet 4.6

Released February 17, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

anthropic logoClaude Sonnet 4.630.1
openai logoGPT-5.2-Codex28.5

Coding index

anthropic logoClaude Sonnet 4.663
openai logoGPT-5.2-CodexNot available

Agentic index

anthropic logoClaude Sonnet 4.631.8
openai logoGPT-5.2-CodexNot available

Pricing

Claude Sonnet 4.6 vs GPT-5.2-Codex API pricing

Per-token API rates. Cheaper option highlighted.

Metricanthropic logoClaude Sonnet 4.6openai logoGPT-5.2-Codex
Input tokensPer 1M tokens$3$1.75
Output tokensPer 1M tokens$15$14
Cached input (read)Per 1M tokens$0.30$0.18
Cache writePer 1M tokens$3.75Not available
Web searchPer request$0.01$0.01

What it costs in practice

Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.

Chat message

2K in, 500 out

anthropic logoClaude Sonnet 4.6$13.50
openai logoGPT-5.2-Codex$10.50

Coding task

30K in, 4K out

anthropic logoClaude Sonnet 4.6$150$69 cached
openai logoGPT-5.2-Codex$108.50$61.25 cached

Long document summary

150K in, 2K out

anthropic logoClaude Sonnet 4.6$480$75 cached
openai logoGPT-5.2-Codex$290.50$54.25 cached

Specs

Context window and capabilities

How much each model can read, how much it can write, and what it accepts as input.

Metricanthropic logoClaude Sonnet 4.6openai logoGPT-5.2-Codex
Context window1M tokens400K tokens
Max output128K tokens128K tokens
Input typesFile, Image, TextImage, Text
Output typesTextText
Reasoning effort levelsMax, High, Medium, LowExtra high, High, Medium, Low
Default reasoning effortMediumMedium
Release dateFebruary 17, 2026January 14, 2026

Features

Supported features

API features available for each model.

Metricanthropic logoClaude Sonnet 4.6openai logoGPT-5.2-Codex
Tool callingSupportedSupported
Structured outputsSupportedSupported
JSON modeSupportedSupported
ReasoningSupportedSupported
TemperatureSupportedNot supported
Stop sequencesSupportedNot supported
Deterministic seedNot supportedSupported
Verbosity controlSupportedSupported

Our take

GPT-5.2-Codex is 1.3x cheaper for a typical chat. Claude Sonnet 4.6 scores higher on the Artificial Analysis Intelligence Index (30.1 vs 28.5). Claude Sonnet 4.6 has the larger context window (1M vs 400K tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.

FAQ

Frequently asked questions

Is Claude Sonnet 4.6 or GPT-5.2-Codex cheaper?

GPT-5.2-Codex is cheaper for a typical chat (2K input tokens and 500 output tokens). GPT-5.2-Codex costs $1.75 per 1M input tokens and $14 per 1M output tokens, while Claude Sonnet 4.6 costs $3 per 1M input tokens and $15 per 1M output tokens.

Which has a bigger context window, Claude Sonnet 4.6 or GPT-5.2-Codex?

Claude Sonnet 4.6 supports up to 1M tokens of context, compared with 400K for GPT-5.2-Codex.

Is Claude Sonnet 4.6 smarter than GPT-5.2-Codex?

On the Artificial Analysis Intelligence Index, Claude Sonnet 4.6 scores 30.1 and GPT-5.2-Codex scores 28.5, putting Claude Sonnet 4.6 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.

Can I use Claude Sonnet 4.6 and GPT-5.2-Codex at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Claude Sonnet 4.6 and GPT-5.2-Codex answer side by side and keep the better response.

anthropic logoopenai logo

Why choose? Ask both.

Send one prompt to Claude Sonnet 4.6 and GPT-5.2-Codex at the same time. Compare the answers side by side and keep the best one.