Claude 3.5 SonnetvsClaude Haiku 4.5

Claude 3.5 Sonnet
Claude Haiku 4.5
API pricing
Input price
$1.00
Output price
$5.00
Cached input price
$0.10
Benchmarks
BullshitBench v2
45%77%
SWE-Bench Verified
33.4%73.3%
GPQA Diamond
59.4%73%
Overview
CompanyAnthropicAnthropic
Release dateJun 20 2024Oct 15 2025
AccessProprietaryProprietary

Frequently asked questions

Claude Haiku 4.5 leads Claude 3.5 Sonnet on 3 of the 3 benchmarks they both report (BullshitBench v2, SWE-Bench Verified, GPQA Diamond). Only Claude Haiku 4.5 has a verified first-party API price: $1.00 per million input tokens and $5.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude 3.5 Sonnet. Claude 3.5 Sonnet shipped 482 days before Claude Haiku 4.5, 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 Claude 3.5 Sonnet at 45%. On SWE-Bench Verified, Claude Haiku 4.5 leads at 73.3% vs Claude 3.5 Sonnet at 33.4%. On GPQA Diamond, Claude Haiku 4.5 leads at 73% vs Claude 3.5 Sonnet at 59.4%.

Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.

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

Claude Haiku 4.5 leads on SWE-Bench Verified — Claude 3.5 Sonnet 33.4% vs Claude Haiku 4.5 73.3%.

Claude Haiku 4.5 leads on GPQA Diamond — Claude 3.5 Sonnet 59.4% vs Claude Haiku 4.5 73%.

Only Claude Haiku 4.5 has a verified first-party API price: $1.00 per million input tokens and $5.00 per million output tokens. No pay-as-you-go API rate is tracked for Claude 3.5 Sonnet. Rates are pay-as-you-go API prices verified on August 18, 2026.

Other comparisons