Claude Opus 5 vs GPT-5.4

Anthropic · US  |  OpenAI · US · Updated June 2026

Quick verdict

Pick Claude Opus 5 for frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1 or agentic coding — within 0.5% of fable 5's peak cursorbench 3.2 score at half the cost per task (anthropic's figures). Pick GPT-5.4 for strong general-purpose default or coding and software engineering. On a tight budget at scale, GPT-5.4 is the value pick.

Claude Opus 5 (Anthropic) and GPT-5.4 (OpenAI) are two of the models people most often weigh against each other in 2026. Claude Opus 5 is anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. GPT-5.4 is openAI's 2026 workhorse — unifies Codex and GPT into a strong default that costs half of GPT-5.5. Their biggest split is price, and the breakdown below shows exactly how that plays out for your workload.

Key differences at a glance

Side-by-side specs

SpecClaude Opus 5GPT-5.4
ProviderAnthropic (US) OpenAI (US)
ReleasedJuly 24, 2026 March 5, 2026
Context window1M (~1,500 pages) 1M (~1,500 pages)
Price (in/out)$5/$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

Frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1

Claude Opus 5

Anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak — and it is the newer of the two.

Agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures)

Claude Opus 5

Claude Opus 5 lists agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures) among its strengths; GPT-5.4 does not.

Computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost

Claude Opus 5

Claude Opus 5 lists computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost among its strengths; GPT-5.4 does not.

Strong general-purpose default

GPT-5.4

OpenAI's 2026 workhorse — unifies Codex and GPT into a strong default that costs half of GPT-5.5 — and it runs cheaper at $2.5/$15 per 1M tokens.

Coding and software engineering

GPT-5.4

Claude Opus 5 is comparatively weak here — no published SWE-Bench Verified score, so head-to-head coding comparisons rely on Anthropic's own benchmark suite

Document understanding and tool use

GPT-5.4

GPT-5.4 lists document understanding and tool use among its strengths; Claude Opus 5 does not.

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 Claude Opus 5, and on millions of tokens that margin decides the monthly bill.

Anyone whose priority is frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1

Claude Opus 5

It is specifically built for that.

Anyone whose priority is strong general-purpose default

GPT-5.4

That is its strongest area.

Claude Opus 5: where it fits

Anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. Released July 24, 2026 by Anthropic, it is built for frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1, agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures), computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost, and a native effort setting (low, medium, high, xhigh, max) that trades token cost against capability on a single model.

Its trade-offs are real: behind Mythos 5 on cybersecurity exploitation and biology research, by Anthropic's own account, all launch benchmarks are Anthropic-reported and not yet independently reproduced, no published SWE-Bench Verified score, so head-to-head coding comparisons rely on Anthropic's own benchmark suite, and fast mode's throughput costs double the base price ($10/$50 per 1M). At $5 in / $25 out per million tokens, it sits in the premium price band.

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: 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.

The bottom line for this matchup

Claude Opus 5 and GPT-5.4 overlap enough that the right pick depends on your specific job. GPT-5.4 costs less per token; and each leads in its own area — Claude Opus 5 for frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1, GPT-5.4 for strong general-purpose default. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Claude Opus 5 and GPT-5.4 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Claude Opus 5 or GPT-5.4 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, Claude Opus 5 leans toward frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1 while GPT-5.4 leans toward strong general-purpose default, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Opus 5 or GPT-5.4?

GPT-5.4 is cheaper — $5/$25 per 1M tokens vs $2.5/$15 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.

Can I use both Claude Opus 5 and GPT-5.4 together?

Yes — a multi-model platform like LumiChats gives you Claude Opus 5, GPT-5.4 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Claude Opus 5 or GPT-5.4?

Claude Opus 5 — released July 24, 2026, about 5 months 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.