GPT-4.1 vs GPT-5.5 Pro

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 Pro

OpenAI · Apr 2026

The maximum-compute tier of GPT-5.5 for the hardest research, math and engineering problems, at a steep per-token premium.

The verdict

These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GPT-4.1 works out roughly 19x cheaper per blended million tokens.

Specs & pricing

GPT-4.1GPT-5.5 Pro
modhub Index
Input price / 1M$2$30
Output price / 1M$8$180
Context window1M1M
Max output33K128K
Open weightsnono
Reasoning modelnoyes
Multimodal inputtext, imagetext, image
Knowledge cutoffJun 2024Jan 2026
ReleasedApr 2025Apr 2026
Example monthly cost*$32.00$570.00

* 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 Pro?
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GPT-4.1 works out roughly 19x cheaper per blended million tokens.
Which is cheaper, GPT-4.1 or GPT-5.5 Pro?
GPT-4.1 costs $2/$8 per million input/output tokens, while GPT-5.5 Pro costs $30/$180. For a typical workload of 10M input and 1.5M output tokens per month, that's $32.00 versus $570.00.
Which model is better for coding, GPT-4.1 or GPT-5.5 Pro?
We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.

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