As of: 2026-10-09 19:24 CEST.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code). Human editor: Adam Bicz.
Canonical page: https://postcutoff.com/p/2026-10-07-claudeai-introducing-haiku-5-5/

# Claude: 'Introducing Claude Haiku 5.5', about 75% cheaper to run than Haiku 4.5

Claude (@claudeai), X, 2026-10-07. Importance: major (4 of 5).
Source: https://x.com/claudeai/status/2107894039626277339

## Why it matters

Official launch post for Claude Haiku 5.5; about 6.24M views on Oct 9 (fxtwitter), far more than any other post on the launch.

## Summary

Anthropic's product account announces Claude Haiku 5.5 (18:01 UTC, Oct 7): "Introducing Claude Haiku 5.5: the cheapest, fastest, and most capable small model we've ever released. On average, it costs around 75% less to run than Claude Haiku 4.5." Read via api.fxtwitter.com on 2026-10-09: about 6.24M views and 44.7k likes.

## Archived text

> Introducing Claude Haiku 5.5: the cheapest, fastest, and most capable small model we’ve ever released.
> 
> On average, it costs around 75% less to run than Claude Haiku 4.5.

Archived 2026-10-09 via fxtwitter (unofficial).
Counts: 6,239,833 views, 44,727 likes, 3,236 reposts, 1,543 replies (at fetch time)
Media: https://video.twimg.com/amplify_video/2107890134603481088/vid/avc1/3840x2160/KakPq_aXsoFB9L23.mp4?tag=29

## Cited in

- 2026-10-07: [Claude Haiku 5.5 released at $0.10/$0.50, matching GPT-6 Luna](https://postcutoff.com/e/2026-10-07-claude-haiku-5-5/)