GPT-4o vs GPT-5.1

Side-by-side benchmark comparison across coding, math, reasoning, speed, and pricing.

GPT-5.1 by OpenAI wins on 15 of 17 benchmarks against GPT-4o by OpenAI, which leads on 1. This head-to-head comparison covers coding, math, reasoning, speed, and pricing metrics from our benchmark data.

Category-by-Category Breakdown

General Intelligence: In general intelligence, GPT-5.1 scores 1464 on Chatbot Arena ELO compared to GPT-4o's 1280, while GPT-5.1 scores 86.0% on MMLU-Pro compared to GPT-4o's 72.6%, while GPT-5.1 scores 91.0% on IFEval compared to GPT-4o's 85.3%.

Coding: In coding, GPT-5.1 scores 93.0% on HumanEval+ compared to GPT-4o's 87.2%, while GPT-5.1 scores 76.3% on SWE-bench Verified compared to GPT-4o's 30.7%, while GPT-5.1 scores 82.0% on LiveCodeBench compared to GPT-4o's 38.0%.

Math: In math, GPT-5.1 scores 95.0% on MATH compared to GPT-4o's 74.6%, while GPT-5.1 scores 98.5% on GSM8K compared to GPT-4o's 92.0%, while GPT-5.1 scores 94.0% on AIME 2025 compared to GPT-4o's 9.3%.

Reasoning: In reasoning, GPT-5.1 scores 88.1% on GPQA Diamond compared to GPT-4o's 53.6%, while GPT-5.1 scores 50.0% on ARC-AGI compared to GPT-4o's 5.0%.

Context: In context, GPT-5.1 scores 400K on Context Length compared to GPT-4o's 128K.

Pricing Comparison

GPT-4o costs $2.5/1M input tokens and $10.0/1M output tokens, while GPT-5.1 costs $1.3/1M input and $10.0/1M output. GPT-5.1 is the more affordable option for API usage.

Speed Comparison

GPT-4o generates output at 143 tok/s compared to GPT-5.1's 95 tok/s, and the time to first token is 450 ms for GPT-4o versus 350 ms for GPT-5.1. GPT-4o delivers faster throughput.

Verdict

For developers prioritizing speed, GPT-4o has the edge. For those who value coding and general intelligence and math and affordability, GPT-5.1 is the stronger choice.

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GPT-4o vs GPT-5.1 — FAQ

Which is better, GPT-4o or GPT-5.1?

GPT-5.1 wins on more benchmarks overall (15 vs 1). However, the best choice depends on your specific needs — each model excels in different areas.

How does GPT-4o compare to GPT-5.1 for coding?

GPT-5.1 is better for coding, scoring 76.3% on SWE-bench Verified compared to 30.7%. SWE-bench tests real-world software engineering by resolving actual GitHub issues.

Is GPT-4o cheaper than GPT-5.1?

Yes, GPT-5.1 is cheaper. GPT-4o costs $2.5/1M input and $10.0/1M output tokens. GPT-5.1 costs $1.3/1M input and $10.0/1M output tokens.

Which is faster, GPT-4o or GPT-5.1?

GPT-4o is faster, generating output at 143 tok/s compared to 95 tok/s. Faster output speed means shorter wait times for API responses.

What benchmarks does the GPT-4o vs GPT-5.1 comparison cover?

This comparison covers 17 benchmarks including Chatbot Arena ELO, MMLU-Pro, HumanEval+, IFEval, MATH, GPQA Diamond, SWE-bench Verified, Output Speed, and more. Metrics span general intelligence, coding, math, reasoning, speed, and cost categories.