GPT-5.1 vs GPT-5.2

OpenAI · US  |  OpenAI · US · Updated June 2026

Quick verdict

Both are OpenAI models. GPT-5.2 is the newer, generally stronger default; reach for GPT-5.1 when its lower price or a specific cost or latency profile matters more than the latest capabilities.

GPT-5.1 and GPT-5.2 are both OpenAI models, so the real question is not which lab to trust but which tier fits your workload and budget. GPT-5.1 is openAI's late-2025 GPT-5.1 at $1.25/$10 — a capable general model since surpassed by the GPT-5.2–5.6 line. GPT-5.2 is a capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. 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-5.1GPT-5.2
ProviderOpenAI (US) OpenAI (US)
ReleasedNovember 13, 2025 December 11, 2025
Context window400K (~600 pages) 400K (~600 pages)
Price (in/out)$1.25/$10 per 1M tokens $1.75/$14 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Adaptive reasoning that scales compute to task difficulty

GPT-5.1

At $1.25/$10 per 1M tokens it undercuts GPT-5.2 ($1.75/$14 per 1M tokens), and that gap compounds at volume.

General-purpose reasoning, coding and tool use

GPT-5.1

OpenAI's late-2025 GPT-5.1 at $1.25/$10 — a capable general model since surpassed by the GPT-5.2–5.6 line — and it runs cheaper at $1.25/$10 per 1M tokens.

A large ~400K context for long documents and sessions

GPT-5.1

GPT-5.2 is comparatively weak here — smaller context than flagships

Strong all-round reasoning

GPT-5.2

A capable GPT-5-generation all-rounder, now succeeded by GPT-5.5 — and it is the newer of the two.

Reliable structured output

GPT-5.2

GPT-5.1 is comparatively weak here — premium output price at $10/1M for a now-older model

Broad ecosystem and tooling

GPT-5.2

GPT-5.2 lists broad ecosystem and tooling among its strengths; GPT-5.1 does not.

Lowest cost at scale

GPT-5.1

At $1.25/$10 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Which should you pick?

A cost-sensitive startup shipping high volume

GPT-5.1

At $1.25/$10 per 1M tokens it undercuts GPT-5.2, and on millions of tokens that margin decides the monthly bill.

Anyone whose priority is adaptive reasoning that scales compute to task difficulty

GPT-5.1

It is specifically built for that.

Anyone whose priority is strong all-round reasoning

GPT-5.2

That is its strongest area.

GPT-5.1: where it fits

OpenAI's late-2025 GPT-5.1 at $1.25/$10 — a capable general model since surpassed by the GPT-5.2–5.6 line. Released November 13, 2025 by OpenAI, it is built for adaptive reasoning that scales compute to task difficulty, general-purpose reasoning, coding and tool use, a large ~400K context for long documents and sessions, and text and image input.

Its trade-offs are real: superseded by GPT-5.2 through GPT-5.6 — kept for compatibility rather than being current, no reliably published SWE-Bench Verified figure, exact context window unconfirmed (400K vs 410K across trackers), and premium output price at $10/1M for a now-older model. At $1.25 in / $10 out per million tokens, it sits in the mid price band.

GPT-5.2: where it fits

A capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. Released December 11, 2025 by OpenAI, it is built for strong all-round reasoning, reliable structured output, broad ecosystem and tooling, and professional workflows.

Its trade-offs: superseded by GPT-5.5, and smaller context than flagships. At $1.75 in / $14 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

Because GPT-5.1 and GPT-5.2 come from the same lab (OpenAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. GPT-5.2 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-5.2 and drop down only with a concrete reason.

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Frequently asked questions

Is GPT-5.1 or GPT-5.2 better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, GPT-5.1 leans toward adaptive reasoning that scales compute to task difficulty while GPT-5.2 leans toward strong all-round reasoning, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-5.1 or GPT-5.2?

GPT-5.1 is cheaper — $1.25/$10 per 1M tokens vs $1.75/$14 per 1M tokens, roughly 1.4× apart on input.

Which has the bigger context window?

Both advertise 400K (~600 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.

Should I upgrade from GPT-5.1 to GPT-5.2?

Since both are OpenAI models, the newer one (GPT-5.2) is usually the better default unless you need a specific cost or latency profile from the other.

Which is newer, GPT-5.1 or GPT-5.2?

GPT-5.2 — released December 11, 2025, about 28 days after GPT-5.1.

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.