Claude 3.5 HaikuvsClaude Haiku 4.5

Claude 3.5 Haiku
Claude Haiku 4.5
Benchmarks
Nonsense detection
BullshitBench v2
50%
77%Best
Coding
SWE-Bench Verified
40.6%
73.3%Best
Science
GPQA Diamond
41.6%
73%Best
Overview
CompanyAnthropicAnthropic
Release dateOct 22 2024Oct 15 2025
AccessProprietaryProprietary

Which is better: Claude 3.5 Haiku or Claude Haiku 4.5?

Claude Haiku 4.5 leads Claude 3.5 Haiku on 3 of the 3 benchmarks they both report (BullshitBench v2, SWE-Bench Verified, GPQA Diamond). Claude 3.5 Haiku shipped 358 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 Haiku at 50%. On SWE-Bench Verified, Claude Haiku 4.5 leads at 73.3% vs Claude 3.5 Haiku at 40.6%. On GPQA Diamond, Claude Haiku 4.5 leads at 73% vs Claude 3.5 Haiku at 41.6%.

Frequently asked questions

Claude 3.5 Haiku was released by Anthropic on Oct 22 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 Haiku 40.6% vs Claude Haiku 4.5 73.3%.

Claude Haiku 4.5 leads on GPQA Diamond — Claude 3.5 Haiku 41.6% vs Claude Haiku 4.5 73%.

Other comparisons