Claude Haiku 5.5 vs o1-pro
Claude Haiku 5.5 leads the LLM Stats Score 50.0 to 19.7.
Anthropic · OpenAI · Updated for 2026
Which is better?
Claude Haiku 5.5 leads the overall LLM Stats Score 50.0 to 19.7, ranking #19 overall.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Claude Haiku 5.5
- overall performance matters — it scores 50.0 and ranks #19 on LLM Stats
- your work emphasizes reasoning — it leads those capability indexes
- you want the most recent training data — it shipped Oct 2026
Choose o1-pro
- you are already invested in the OpenAI ecosystem
At a glance
The differences that matter most.
Individual benchmarks
36 reported for Claude Haiku 5.5 · 2 for o1-pro
Claude Haiku 5.5 and o1-prodon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Context Window
Maximum input and output token capacity
Only Claude Haiku 5.5 specifies input context (1,000,000 tokens). Only Claude Haiku 5.5 specifies output context (128,000 tokens).
Input capabilities
Documented input modalities across available providers
Both Claude Haiku 5.5 and o1-pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Haiku 5.5
o1-pro
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude Haiku 5.5 was released on 2026-10-07, while o1-pro was released on 2024-12-17.
Claude Haiku 5.5 is 22 months newer than o1-pro.
Oct 7, 2026
1 days ago
1.8yr newerDec 17, 2024
1.8 years ago
Knowledge Cutoff
When training data ends
Claude Haiku 5.5 has a knowledge cutoff of 2026-06-01, while o1-pro has a cutoff of 2023-09-30.
Claude Haiku 5.5 has more recent training data (up to 2026-06-01), making it potentially better informed about events through that date compared to o1-pro (2023-09-30).
Jun 2026
2.8 yr newerSep 2023
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Haiku 5.5 and o1-pro side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Haiku 5.5 vs o1-pro.