GPT-5.4 vs GPT-5.5

OpenAI · US  |  OpenAI · US · Updated June 2026

Quick verdict

Both are OpenAI models. GPT-5.5 is the newer, generally stronger default; reach for GPT-5.4 when its lower price or specific profile matters more than the latest capabilities.

GPT-5.4 and GPT-5.5 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 is openAI's 2026 workhorse — unifies Codex and GPT into a strong default that costs half of GPT-5.5. GPT-5.5 is openAI's first fully retrained base since GPT-4.5 — the terminal and computer-use champion. 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-5.4GPT-5.5
ProviderOpenAI (US) OpenAI (US)
ReleasedMarch 5, 2026 April 23, 2026
Context window1M (~1,500 pages) 1M (~1,500 pages)
Price (in/out)$2.5/$15 per 1M tokens $5/$30 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, audio, video, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Strong general-purpose default

GPT-5.4

A core design strength of GPT-5.4.

Coding and software engineering

GPT-5.4

A core design strength of GPT-5.4.

Document understanding and tool use

GPT-5.4

A core design strength of GPT-5.4.

Terminal, CLI and computer-use automation

GPT-5.5

A core design strength of GPT-5.5.

Long-horizon tool sequencing

GPT-5.5

A core design strength of GPT-5.5.

Natively omnimodal input

GPT-5.5

A core design strength of GPT-5.5.

Lowest cost at scale

GPT-5.4

At $2.5/$15 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-5.4

At $2.5/$15 per 1M tokens it undercuts GPT-5.5, and on millions of tokens that margin decides the monthly bill.

Anyone whose priority is strong general-purpose default

GPT-5.4

It is specifically built for that.

Anyone whose priority is terminal, cli and computer-use automation

GPT-5.5

That is its strongest area.

GPT-5.4: where it fits

OpenAI's 2026 workhorse — unifies Codex and GPT into a strong default that costs half of GPT-5.5. Released March 5, 2026 by OpenAI, it is built for strong general-purpose default, coding and software engineering, document understanding and tool use, and 1M context with good token efficiency.

Its trade-offs are real: topped by GPT-5.5 on the hardest tasks, and pricier than open-weight rivals. At $2.5 in / $15 out per million tokens, it sits in the mid price band.

GPT-5.5: where it fits

OpenAI's first fully retrained base since GPT-4.5 — the terminal and computer-use champion. Released April 23, 2026 by OpenAI, it is built for terminal, CLI and computer-use automation, long-horizon tool sequencing, natively omnimodal input, and browser-driving agents.

Its trade-offs: trails Opus 4.8 on hardest coding benchmarks, and tiered long-context pricing above 272K tokens. At $5 in / $30 out per million tokens, it sits in the premium price band.

The bottom line for this matchup

Because GPT-5.4 and GPT-5.5 come from the same lab (OpenAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. GPT-5.5 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-5.5 and drop down only with a concrete reason.

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Frequently asked questions

Is GPT-5.4 or GPT-5.5 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 leans toward strong general-purpose default while GPT-5.5 leans toward terminal, cli and computer-use automation, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-5.4 or GPT-5.5?

GPT-5.4 is cheaper — $2.5/$15 per 1M tokens vs $5/$30 per 1M tokens, roughly 2× apart on input.

Which has the bigger context window?

Both advertise 1M (~1,500 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.

Should I upgrade from GPT-5.4 to GPT-5.5?

Since both are OpenAI models, the newer one (GPT-5.5) is usually the better default unless you need a specific cost or latency profile from the other.

Which is newer, GPT-5.4 or GPT-5.5?

GPT-5.5 — released April 23, 2026, about 49 days after GPT-5.4.

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.