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Claude 3.5 Haiku vs Phi 4 Reasoning Plus

Phi 4 Reasoning Plus leads the LLM Stats Score 15.0 to 5.2.

Anthropic · Microsoft · Updated for 2026

Which is better?

Phi 4 Reasoning Plus leads the overall LLM Stats Score 15.0 to 5.2, ranking #230 overall.

In the 2 individual benchmarks reported for both models, Phi 4 Reasoning Plus wins 2; this is a narrower head-to-head signal than the composite indexes.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude 3.5 Haiku

  • you want predictable pricing at $0.80/M input and $4.00/M output

Choose Phi 4 Reasoning Plus

  • overall performance matters — it scores 15.0 and ranks #230 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 2 of 2 exact shared results
  • you want the most recent training data — it shipped Apr 2025
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Core performance indexes
5.2
#297
15.0
#230
5.4
#293
15.4
#224
4.2
#210
5.7
#195
Cost, coverage & limits
Benchmark wins
0 of 2
2 of 2
Input price
$0.80 / M
— / M
Output price
$4.00 / M
— / M
Context window
200,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Claude 3.5 Haiku
Phi 4 Reasoning Plus
10.6#250
18.3#182
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

9 reported for Claude 3.5 Haiku · 11 for Phi 4 Reasoning Plus

2 shared

Claude 3.5 Haiku outperforms in 0 benchmarks, while Phi 4 Reasoning Plus is better at 2 benchmarks (GPQA, MMLU-Pro).

Phi 4 Reasoning Plus significantly outperforms across most benchmarks.

Sun Sep 13 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Claude 3.5 Haiku specifies input context (200,000 tokens). Only Claude 3.5 Haiku specifies output context (200,000 tokens).

Anthropic
Claude 3.5 Haiku
Input200,000 tokens
Output200,000 tokens
Microsoft
Phi 4 Reasoning Plus
Input- tokens
Output- tokens
Sun Sep 13 2026 • llm-stats.com

License

Usage and distribution terms

Claude 3.5 Haiku is licensed under a proprietary license, while Phi 4 Reasoning Plus uses MIT.

License differences may affect how you can use these models in commercial or open-source projects.

Claude 3.5 Haiku

Proprietary

Closed source

Phi 4 Reasoning Plus

MIT

Open weights

Release Timeline

When each model was launched

Claude 3.5 Haiku was released on 2024-10-22, while Phi 4 Reasoning Plus was released on 2025-04-30.

Phi 4 Reasoning Plus is 6 months newer than Claude 3.5 Haiku.

Claude 3.5 Haiku

Oct 22, 2024

1.9 years ago

Phi 4 Reasoning Plus

Apr 30, 2025

1.4 years ago

6mo newer

Knowledge Cutoff

When training data ends

Phi 4 Reasoning Plus has a documented knowledge cutoff of 2025-03-01, while Claude 3.5 Haiku's cutoff date is not specified.

We can confirm Phi 4 Reasoning Plus's training data extends to 2025-03-01, but cannot make a direct comparison without Claude 3.5 Haiku's cutoff date.

Claude 3.5 Haiku

Phi 4 Reasoning Plus

Mar 2025

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Claude 3.5 Haiku and Phi 4 Reasoning Plus side-by-side, then vote on the output you prefer.

Claude 3.5 Haiku
✓ Preferred
Phi 4 Reasoning Plus
Open in Playground

FAQ

Common questions about Claude 3.5 Haiku vs Phi 4 Reasoning Plus.

Which is better, Claude 3.5 Haiku or Phi 4 Reasoning Plus?

Phi 4 Reasoning Plus leads the LLM Stats Score 15.0 to 5.2. Claude 3.5 Haiku is made by Anthropic and Phi 4 Reasoning Plus is made by Microsoft. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude 3.5 Haiku compare to Phi 4 Reasoning Plus in benchmarks?

Claude 3.5 Haiku scores HumanEval: 88.1%, MGSM: 85.6%, DROP: 83.1%, MATH: 69.4%, MMLU-Pro: 65.0%. Phi 4 Reasoning Plus scores FlenQA: 97.9%, HumanEval+: 92.3%, IFEval: 84.9%, OmniMath: 81.9%, AIME 2024: 81.3%.

What are the context window sizes for Claude 3.5 Haiku and Phi 4 Reasoning Plus?

Claude 3.5 Haiku supports 200K tokens and Phi 4 Reasoning Plus supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude 3.5 Haiku and Phi 4 Reasoning Plus?

Key differences include LLM Stats Score (5.2 vs 15.0), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude 3.5 Haiku and Phi 4 Reasoning Plus?

Claude 3.5 Haiku is developed by Anthropic and Phi 4 Reasoning Plus is developed by Microsoft.