GPT-4.1 vs GPT-5.5

Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.

GPT-4.1

OpenAI · Apr 2025

A non-reasoning workhorse with a 1M-token context window, still popular for predictable-latency production APIs.

GPT-5.5

OpenAI · Apr 2026

77.2

OpenAI's flagship reasoning model with a 1M-token context window, built for hard coding, science and long-horizon agentic work.

The verdict

GPT-5.5 wins 2 of the 2 benchmarks these models share, against 0 for GPT-4.1. On price the gap is dramatic: GPT-4.1 works out roughly 3.2x cheaper per blended million tokens.

Benchmark head-to-head 02

SWE-bench Verified
54.6%82.6%
GPT-4.1GPT-5.5
GPQA Diamond
66.3%~92%
GPT-4.1GPT-5.5

Specs & pricing

GPT-4.1GPT-5.5
modhub Index77.2
Input price / 1M$2$5
Output price / 1M$8$30
Context window1M1M
Max output33K128K
Open weightsnono
Reasoning modelnoyes
Multimodal inputtext, imagetext, image
Knowledge cutoffJun 2024Jan 2026
ReleasedApr 2025Apr 2026
Example monthly cost*$32.00$95.00

* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.

Frequently asked questions

Which is better, GPT-4.1 or GPT-5.5?
GPT-5.5 wins 2 of the 2 benchmarks these models share, against 0 for GPT-4.1. On price the gap is dramatic: GPT-4.1 works out roughly 3.2x cheaper per blended million tokens.
Which is cheaper, GPT-4.1 or GPT-5.5?
GPT-4.1 costs $2/$8 per million input/output tokens, while GPT-5.5 costs $5/$30. For a typical workload of 10M input and 1.5M output tokens per month, that's $32.00 versus $95.00.
Which model is better for coding, GPT-4.1 or GPT-5.5?
On SWE-bench Verified — the standard agentic-coding benchmark — GPT-5.5 scores 82.6% versus 54.6% for GPT-4.1, making GPT-5.5 the stronger pick for coding agents.

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