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 Mini for free for every chatgpt user or fast, low-cost general tasks. On a tight budget at scale, GPT-5.4 Mini is the value pick.
Claude Opus 5 (Anthropic) and GPT-5.4 Mini (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 Mini is openAI's free, fast workhorse — capable general AI with no subscription needed. They diverge most on price and context window — each quantified below from the models' real specs.
Key differences
Price: GPT-5.4 Mini is about 6.7× cheaper on input ($0.75/$4.5 per 1M tokens vs $5/$25 per 1M tokens) — a large enough gap that at scale it can be the single biggest line item in the decision.
Context window: Claude Opus 5 holds 2.5× more — 1M (~1,500 pages) vs 400K (~600 pages). But effective recall usually fades long before the advertised ceiling, so the bigger number only helps if the model reasons over it.
Recency: Claude Opus 5 is the newer model by about 4 months (released July 24, 2026), usually meaning fresher training data and capabilities.
Specifications
Spec
Claude Opus 5
GPT-5.4 Mini
Provider
Anthropic (US)
OpenAI (US)
Released
July 24, 2026
March 17, 2026
Context window
1M (~1,500 pages)
400K (~600 pages)
Price (in/out)
$5/$25 per 1M tokens
$0.75/$4.5 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image, code
text, image, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not 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 — GPT-5.4 Mini is comparatively weak here — not for the hardest reasoning
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 — 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 carries the larger 1M context.
Computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost: 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.
Free for every ChatGPT user: GPT-5.4 Mini — OpenAI's free, fast workhorse — capable general AI with no subscription needed — and it runs cheaper at $0.75/$4.5 per 1M tokens.
Fast, low-cost general tasks: GPT-5.4 Mini — At $0.75/$4.5 per 1M tokens it undercuts Claude Opus 5 ($5/$25 per 1M tokens), and that gap compounds at volume.
Subagent capabilities: GPT-5.4 Mini — GPT-5.4 Mini lists subagent capabilities among its strengths; Claude Opus 5 does not.
Lowest cost at scale: GPT-5.4 Mini — At $0.75/$4.5 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Largest single-prompt input: Claude Opus 5 — Its 1M window is about 2.5× larger than GPT-5.4 Mini's 400K, fitting roughly 1,500 pages in one prompt.
Which should you pick?
A cost-sensitive startup shipping high volume: GPT-5.4 Mini — At $0.75/$4.5 per 1M tokens it undercuts Claude Opus 5, and on millions of tokens that margin decides the monthly bill.
Someone analysing very long documents or codebases: Claude Opus 5 — Larger 1M window fits more in one prompt.
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 free for every chatgpt user: GPT-5.4 Mini — 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 Mini: where it fits
OpenAI's free, fast workhorse — capable general AI with no subscription needed. Released March 17, 2026 by OpenAI, it is built for free for every ChatGPT user, fast, low-cost general tasks, subagent capabilities, and native multimodal reasoning.
Its trade-offs: smaller context than flagship models, and not for the hardest reasoning. At $0.75 in / $4.5 out per million tokens, it sits in the budget price band.
The bottom line for this matchup
Claude Opus 5 and GPT-5.4 Mini overlap enough that the right pick depends on your specific job. GPT-5.4 Mini costs less per token; Claude Opus 5 holds the larger context; 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 Mini for free for every chatgpt user. Rather than crowning one, run the same hard task through both once and let the results decide.
Frequently asked questions
Is Claude Opus 5 or GPT-5.4 Mini 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 Mini leans toward free for every chatgpt user, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Claude Opus 5 or GPT-5.4 Mini?
GPT-5.4 Mini is cheaper — $5/$25 per 1M tokens vs $0.75/$4.5 per 1M tokens, roughly 6.7× apart on input.
Which has the bigger context window?
Claude Opus 5 — 1M vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.
Can I use both Claude Opus 5 and GPT-5.4 Mini together?
Yes — a multi-model platform like LumiChats gives you Claude Opus 5, GPT-5.4 Mini 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 Mini?
Claude Opus 5 — released July 24, 2026, about 4 months after GPT-5.4 Mini.
Claude Opus 5 vs GPT-5.4 Mini
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 Mini for free for every chatgpt user or fast, low-cost general tasks. On a tight budget at scale, GPT-5.4 Mini is the value pick.
Claude Opus 5 (Anthropic) and GPT-5.4 Mini (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 Mini is openAI's free, fast workhorse — capable general AI with no subscription needed. They diverge most on price and context window — each quantified below from the models' real specs.
Key differences at a glance
▸Price: GPT-5.4 Mini is about 6.7× cheaper on input ($0.75/$4.5 per 1M tokens vs $5/$25 per 1M tokens) — a large enough gap that at scale it can be the single biggest line item in the decision.
▸Context window: Claude Opus 5 holds 2.5× more — 1M (~1,500 pages) vs 400K (~600 pages). But effective recall usually fades long before the advertised ceiling, so the bigger number only helps if the model reasons over it.
▸Recency: Claude Opus 5 is the newer model by about 4 months (released July 24, 2026), usually meaning fresher training data and capabilities.
Side-by-side specs
Spec
Claude Opus 5
GPT-5.4 Mini
Provider
Anthropic (US)
OpenAI (US)
Released
July 24, 2026
March 17, 2026
Context window
1M (~1,500 pages)
400K (~600 pages)
Price (in/out)
$5/$25 per 1M tokens
$0.75/$4.5 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image, code
text, image, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not 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
GPT-5.4 Mini is comparatively weak here — not for the hardest reasoning
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
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 carries the larger 1M context.
Computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost
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.
Free for every ChatGPT user
GPT-5.4 Mini
OpenAI's free, fast workhorse — capable general AI with no subscription needed — and it runs cheaper at $0.75/$4.5 per 1M tokens.
Fast, low-cost general tasks
GPT-5.4 Mini
At $0.75/$4.5 per 1M tokens it undercuts Claude Opus 5 ($5/$25 per 1M tokens), and that gap compounds at volume.
Subagent capabilities
GPT-5.4 Mini
GPT-5.4 Mini lists subagent capabilities among its strengths; Claude Opus 5 does not.
Lowest cost at scale
GPT-5.4 Mini
At $0.75/$4.5 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Largest single-prompt input
Claude Opus 5
Its 1M window is about 2.5× larger than GPT-5.4 Mini's 400K, fitting roughly 1,500 pages in one prompt.
Which should you pick?
A cost-sensitive startup shipping high volume
→ GPT-5.4 Mini
At $0.75/$4.5 per 1M tokens it undercuts Claude Opus 5, and on millions of tokens that margin decides the monthly bill.
Someone analysing very long documents or codebases
→ Claude Opus 5
Larger 1M window fits more in one prompt.
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 free for every chatgpt user
→ GPT-5.4 Mini
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 Mini: where it fits
OpenAI's free, fast workhorse — capable general AI with no subscription needed. Released March 17, 2026 by OpenAI, it is built for free for every ChatGPT user, fast, low-cost general tasks, subagent capabilities, and native multimodal reasoning.
Its trade-offs: smaller context than flagship models, and not for the hardest reasoning. At $0.75 in / $4.5 out per million tokens, it sits in the budget price band.
The bottom line for this matchup
Claude Opus 5 and GPT-5.4 Mini overlap enough that the right pick depends on your specific job. GPT-5.4 Mini costs less per token; Claude Opus 5 holds the larger context; 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 Mini for free for every chatgpt user. 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 Mini 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.
Is Claude Opus 5 or GPT-5.4 Mini 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 Mini leans toward free for every chatgpt user, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Claude Opus 5 or GPT-5.4 Mini?
GPT-5.4 Mini is cheaper — $5/$25 per 1M tokens vs $0.75/$4.5 per 1M tokens, roughly 6.7× apart on input.
Which has the bigger context window?
Claude Opus 5 — 1M vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.
Can I use both Claude Opus 5 and GPT-5.4 Mini together?
Yes — a multi-model platform like LumiChats gives you Claude Opus 5, GPT-5.4 Mini 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 Mini?
Claude Opus 5 — released July 24, 2026, about 4 months after GPT-5.4 Mini.
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.