Claude Haiku 4.5vsGPT-5.3-Codex

Claude Haiku 4.5
GPT-5.3-Codex
API pricing
Input price
$1.00$1.75
Output price
$5.00$14.00
Cached input price
$0.10$0.175
Cheapest input
$1.00Amazon Bedrock$1.75Azure
Cheapest output
$5.00Amazon Bedrock$14.00Azure
Benchmarks
BullshitBench v2
77%24%
SWE-Bench Verified
73.3%85%
Benchmarks
Next.js Evals
81%
GPQA Diamond
73%
Overview
CompanyAnthropicOpenAI
Release dateOct 15 2025Feb 5 2026
AccessProprietaryProprietary

Other comparisons

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Frequently asked questions

Claude Haiku 4.5 and GPT-5.3-Codex are evenly matched across the 2 benchmarks they both report (BullshitBench v2, SWE-Bench Verified). Claude Haiku 4.5 is cheaper on both input and output: $1.00 vs $1.75 per million input tokens, and $5.00 vs $14.00 per million output tokens. Claude Haiku 4.5 shipped 113 days before GPT-5.3-Codex, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

On BullshitBench v2, Claude Haiku 4.5 leads at 77% vs GPT-5.3-Codex at 24%. On SWE-Bench Verified, GPT-5.3-Codex leads at 85% vs Claude Haiku 4.5 at 73.3%.

Claude Haiku 4.5 was released by Anthropic on Oct 15 2025.

GPT-5.3-Codex was released by OpenAI on Feb 5 2026.

GPT-5.3-Codex leads on SWE-Bench Verified — Claude Haiku 4.5 73.3% vs GPT-5.3-Codex 85%.

Claude Haiku 4.5 is cheaper on both input and output: $1.00 vs $1.75 per million input tokens, and $5.00 vs $14.00 per million output tokens. Rates are pay-as-you-go API prices verified on August 18, 2026.