GPT-5.4 Nano vs GPT-5.6 Terra

OpenAI · US  |  OpenAI · US · Updated June 2026

Quick verdict

Both are OpenAI models. GPT-5.6 Terra is the newer, generally stronger default; reach for GPT-5.4 Nano when its lower price or a specific cost or latency profile matters more than the latest capabilities.

GPT-5.4 Nano and GPT-5.6 Terra are both OpenAI models, so the real question is not which lab to trust but which tier fits your workload and budget. GPT-5.4 Nano is openAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. GPT-5.6 Terra is the mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost. 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-5.4 NanoGPT-5.6 Terra
ProviderOpenAI (US) OpenAI (US)
ReleasedMarch 17, 2026 July 9, 2026
Context window400K (~600 pages) 1M (~1,500 pages)
Price (in/out)$0.2/$1.25 per 1M tokens $2.5/$15 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

Cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

GPT-5.4 Nano

At $0.2/$1.25 per 1M tokens it undercuts GPT-5.6 Terra ($2.5/$15 per 1M tokens), and that gap compounds at volume.

Classification, extraction, ranking and sub-agent execution at scale

GPT-5.4 Nano

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning — and it runs cheaper at $0.2/$1.25 per 1M tokens.

A 400K context in the smallest, fastest GPT-5.4 variant

GPT-5.4 Nano

GPT-5.4 Nano lists a 400K context in the smallest, fastest GPT-5.4 variant among its strengths; GPT-5.6 Terra does not.

Balanced everyday work at roughly half of Sol's price

GPT-5.6 Terra

The mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost — and it carries the larger 1M context.

Competitive with GPT-5.5 quality at about 2x lower cost

GPT-5.6 Terra

The mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost — and it is the newer of the two.

Solid agentic coding (Terminal-Bench 2.1 in the mid-80s)

GPT-5.6 Terra

GPT-5.4 Nano is comparatively weak here — a nano tier — not built for hard reasoning or frontier coding

Lowest cost at scale

GPT-5.4 Nano

At $0.2/$1.25 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

GPT-5.6 Terra

Its 1M window is about 2.5× larger than GPT-5.4 Nano's 400K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

GPT-5.4 Nano

At $0.2/$1.25 per 1M tokens it undercuts GPT-5.6 Terra, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

GPT-5.6 Terra

Larger 1M window fits more in one prompt.

Anyone whose priority is cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

GPT-5.4 Nano

It is specifically built for that.

Anyone whose priority is balanced everyday work at roughly half of sol's price

GPT-5.6 Terra

That is its strongest area.

GPT-5.4 Nano: where it fits

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. Released March 17, 2026 by OpenAI, it is built for cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work, classification, extraction, ranking and sub-agent execution at scale, a 400K context in the smallest, fastest GPT-5.4 variant, and text and image input for cheap multimodal pipelines.

Its trade-offs are real: a nano tier — not built for hard reasoning or frontier coding, no published SWE-Bench Verified score (OpenAI reported SWE-Bench Pro instead), outclassed by GPT-5.4 and GPT-5.4 Mini whenever a task needs real depth, and image input only — no audio or video. At $0.2 in / $1.25 out per million tokens, it sits in the budget price band.

GPT-5.6 Terra: where it fits

The mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost. Released July 9, 2026 by OpenAI, it is built for balanced everyday work at roughly half of Sol's price, competitive with GPT-5.5 quality at about 2x lower cost, solid agentic coding (Terminal-Bench 2.1 in the mid-80s), and same 1M context and programmatic tool calling as Sol.

Its trade-offs: fewer independently verified benchmarks than Sol, and trails it across coding evals, and no open weights. At $2.5 in / $15 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

Because GPT-5.4 Nano and GPT-5.6 Terra come from the same lab (OpenAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. GPT-5.6 Terra 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-5.6 Terra and drop down only with a concrete reason.

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Frequently asked questions

Is GPT-5.4 Nano or GPT-5.6 Terra 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-5.4 Nano leans toward cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work while GPT-5.6 Terra leans toward balanced everyday work at roughly half of sol's price, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-5.4 Nano or GPT-5.6 Terra?

GPT-5.4 Nano is cheaper — $0.2/$1.25 per 1M tokens vs $2.5/$15 per 1M tokens, roughly 13× apart on input.

Which has the bigger context window?

GPT-5.6 Terra — 1M vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.

Should I upgrade from GPT-5.4 Nano to GPT-5.6 Terra?

Since both are OpenAI models, the newer one (GPT-5.6 Terra) is usually the better default unless you need a specific cost or latency profile from the other.

Which is newer, GPT-5.4 Nano or GPT-5.6 Terra?

GPT-5.6 Terra — released July 9, 2026, about 4 months after GPT-5.4 Nano.

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.