Claude Haiku 5.5 vs GPT-5.1 Codex Mini
Claude Haiku 5.5 leads the LLM Stats Score 49.9 to -3.1. Claude Haiku 5.5 is 3.4x cheaper per token.
Anthropic · OpenAI · Updated for 2026
Which is better?
Claude Haiku 5.5 leads the overall LLM Stats Score 49.9 to -3.1, ranking #20 overall.
On price, Claude Haiku 5.5 is roughly 3.4x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Claude Haiku 5.5 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Claude Haiku 5.5
- overall performance matters — it scores 49.9 and ranks #20 on LLM Stats
- your work emphasizes reasoning — it leads those capability indexes
- cost matters — it's about 3.4x cheaper per token
- you process long inputs — it offers a 1,000,000 token context window
- you want the most recent training data — it shipped Oct 2026
Choose GPT-5.1 Codex Mini
- you want predictable pricing at $0.25/M input and $2.00/M output
At a glance
The differences that matter most.
Individual benchmarks
36 reported for Claude Haiku 5.5 · 1 for GPT-5.1 Codex Mini
Claude Haiku 5.5 and GPT-5.1 Codex Minidon'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
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Haiku 5.5 ($0.10/1M tokens) is 2.5x cheaper than GPT-5.1 Codex Mini ($0.25/1M tokens).
For output processing, Claude Haiku 5.5 ($0.50/1M tokens) is 4.0x cheaper than GPT-5.1 Codex Mini ($2.00/1M tokens).
In conclusion, GPT-5.1 Codex Mini is more expensive than Claude Haiku 5.5.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Claude Haiku 5.5 accepts 1,000,000 input tokens compared to GPT-5.1 Codex Mini's 400,000 tokens. Both models can generate responses up to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Both Claude Haiku 5.5 and GPT-5.1 Codex Mini support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Haiku 5.5
GPT-5.1 Codex Mini
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 GPT-5.1 Codex Mini was released on 2025-11-12.
Claude Haiku 5.5 is 11 months newer than GPT-5.1 Codex Mini.
Oct 7, 2026
2 weeks ago
10mo newerNov 12, 2025
11 months ago
Knowledge Cutoff
When training data ends
Claude Haiku 5.5 has a documented knowledge cutoff of 2026-06-01, while GPT-5.1 Codex Mini's cutoff date is not specified.
We can confirm Claude Haiku 5.5's training data extends to 2026-06-01, but cannot make a direct comparison without GPT-5.1 Codex Mini's cutoff date.
Jun 2026
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Provider Availability
Claude Haiku 5.5 is available from Anthropic. GPT-5.1 Codex Mini is available from OpenAI.
Claude Haiku 5.5
GPT-5.1 Codex Mini
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Haiku 5.5 and GPT-5.1 Codex Mini side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Haiku 5.5 vs GPT-5.1 Codex Mini.