GPT-4.1 Mini vs gpt-oss-120b

OpenAI · US  |  OpenAI · US · Updated June 2026

Quick verdict

Both are OpenAI models. gpt-oss-120b is the newer, generally stronger default; reach for GPT-4.1 Mini when a specific cost or latency profile matters more than the latest capabilities.

GPT-4.1 Mini and gpt-oss-120b are both OpenAI models, so the real question is not which lab to trust but which tier fits your workload and budget. GPT-4.1 Mini is a cheap, fast 1M-context workhorse with strong instruction following but weak coding — already retired from ChatGPT. gpt-oss-120b is openAI's open-weight 117B-parameter MoE reasoning model (5.1B active) that runs on a single 80GB GPU and approaches o4-mini on reasoning, coding, and tool use. Since both come from the same lab, the comparison below focuses on the tier-and-cost trade-offs that actually separate them.

Key differences at a glance

Side-by-side specs

SpecGPT-4.1 Minigpt-oss-120b
ProviderOpenAI (US) OpenAI (US)
ReleasedApril 14, 2025 August 5, 2025
Context window1M (~1,571 pages) 131K (~197 pages)
Price (in/out)$0.4/$1.6 per 1M tokens Open weight (self-host / free)
Open weight?No — API only Yes — self-hostable
Modalitiestext, image, code text, code
SWE-Bench Verified23.6% 62.4%
MRCR v2 @ 1MNot published Not published

Who wins what

Very cheap high-volume text work at $0.40 in / $1.60 out per million tokens

GPT-4.1 Mini

Its 1M window holds about 8× more than gpt-oss-120b's 131K in a single prompt.

Instruction following above its weight class — 84.1% on IFEval, beating GPT-4o

GPT-4.1 Mini

A cheap, fast 1M-context workhorse with strong instruction following but weak coding — already retired from ChatGPT — and it carries the larger 1M context.

Multi-turn coherence for its tier — 35.8% on MultiChallenge, roughly 1.8x GPT-4o mini

GPT-4.1 Mini

GPT-4.1 Mini lists multi-turn coherence for its tier — 35.8% on MultiChallenge, roughly 1.8x GPT-4o mini among its strengths; gpt-oss-120b does not.

Self-hostable on a single 80GB H100 GPU via MXFP4

gpt-oss-120b

Open weights make this possible at all — GPT-4.1 Mini is API-only, so it cannot leave the vendor's servers.

Configurable reasoning depth (low/medium/high)

gpt-oss-120b

GPT-4.1 Mini is comparatively weak here — a June 2024 knowledge cutoff, now roughly two years stale, and no reasoning mode

Agentic tool use, function calling, and code execution

gpt-oss-120b

It scores 62.4% on SWE-Bench Verified against GPT-4.1 Mini's 23.6% — a 38.8-point edge on real repository work.

Lowest cost at scale

gpt-oss-120b

Its weights are open, so at volume you pay for your own hardware instead of GPT-4.1 Mini's $0.4/$1.6 per 1M tokens.

Largest single-prompt input

GPT-4.1 Mini

Its 1M window is about 8× larger than gpt-oss-120b's 131K, fitting roughly 1,571 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

gpt-oss-120b

At Open weight (self-host / free) it undercuts GPT-4.1 Mini, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

GPT-4.1 Mini

Larger 1M window fits more in one prompt.

A team with data-privacy or self-hosting needs

gpt-oss-120b

Open weights let you run it on your own hardware; GPT-4.1 Mini is API-only.

Anyone whose priority is very cheap high-volume text work at $0.40 in / $1.60 out per million tokens

GPT-4.1 Mini

It is specifically built for that.

Anyone whose priority is self-hostable on a single 80gb h100 gpu via mxfp4

gpt-oss-120b

That is its strongest area.

GPT-4.1 Mini: where it fits

A cheap, fast 1M-context workhorse with strong instruction following but weak coding — already retired from ChatGPT. Released April 14, 2025 by OpenAI, it is built for very cheap high-volume text work at $0.40 in / $1.60 out per million tokens, instruction following above its weight class — 84.1% on IFEval, beating GPT-4o, multi-turn coherence for its tier — 35.8% on MultiChallenge, roughly 1.8x GPT-4o mini, and a full 1M context at flat pricing, with no long-context premium.

Its trade-offs are real: weak at agentic coding — its 23.6% on SWE-Bench Verified sits below GPT-4o's 33.2%, retired from ChatGPT in February 2026, and OpenAI's own docs now point users to GPT-5 mini instead, and a June 2024 knowledge cutoff, now roughly two years stale, and no reasoning mode. At $0.4 in / $1.6 out per million tokens, it sits in the budget price band.

gpt-oss-120b: where it fits

OpenAI's open-weight 117B-parameter MoE reasoning model (5.1B active) that runs on a single 80GB GPU and approaches o4-mini on reasoning, coding, and tool use. Released August 5, 2025 by OpenAI, it is built for self-hostable on a single 80GB H100 GPU via MXFP4, configurable reasoning depth (low/medium/high), agentic tool use, function calling, and code execution, and full chain-of-thought visibility for debugging.

Its trade-offs: text-only, no image, audio, or video input, and 131K context and 5.1B active params trail the largest frontier closed models. As an open-weight model, its running cost is your own hardware rather than a per-token fee.

The bottom line for this matchup

Because GPT-4.1 Mini and gpt-oss-120b come from the same lab (OpenAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. gpt-oss-120b is the more capable, more recent option; the other earns its place only when its price or latency profile fits a specific job better. Most teams should default to gpt-oss-120b and drop down only with a concrete reason.

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See pricing

Frequently asked questions

Is GPT-4.1 Mini or gpt-oss-120b better for coding?

On SWE-Bench Verified, GPT-4.1 Mini scores 23.6% and gpt-oss-120b scores 62.4% — gpt-oss-120b has the measurable edge.

Which is cheaper, GPT-4.1 Mini or gpt-oss-120b?

gpt-oss-120b is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while GPT-4.1 Mini is API-metered at $0.4/$1.6 per 1M tokens. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

GPT-4.1 Mini — 1M vs 131K, about 8× larger. Useful only if the model actually reasons over the full window, which not all do.

Should I upgrade from GPT-4.1 Mini to gpt-oss-120b?

Since both are OpenAI models, the newer one (gpt-oss-120b) is usually the better default unless you need a specific cost or latency profile from the other.

Which is newer, GPT-4.1 Mini or gpt-oss-120b?

gpt-oss-120b — released August 5, 2025, about 4 months after GPT-4.1 Mini.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.