Pick Claude Sonnet 5 for agentic workflows that plan, use tools, and run autonomously or multi-step coding, debugging, and tool use. 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 Sonnet 5 (Anthropic) and GPT-5.4 (OpenAI) are two of the models people most often weigh against each other in 2026. Claude Sonnet 5 is anthropic's most agentic Sonnet, with near-Opus-4.8 performance at Sonnet prices; the default model on Free and Pro. 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
Price: nearly identical — $3/$15 per 1M tokens vs $2.5/$15 per 1M tokens. Cost will not be the deciding factor here.
Context window: both advertise 1M (~1,500 pages). Tie on paper — test on your own long inputs, since usable recall varies by model.
Recency: Claude Sonnet 5 is the newer model by about 4 months (released June 30, 2026), usually meaning fresher training data and capabilities.
Specifications
Spec
Claude Sonnet 5
GPT-5.4
Provider
Anthropic (US)
OpenAI (US)
Released
June 30, 2026
March 5, 2026
Context window
1M (~1,500 pages)
1M (~1,500 pages)
Price (in/out)
$3/$15 per 1M tokens
$2.5/$15 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
Agentic workflows that plan, use tools, and run autonomously: Claude Sonnet 5 — A core design strength of Claude Sonnet 5.
Multi-step coding, debugging, and tool use: Claude Sonnet 5 — A core design strength of Claude Sonnet 5.
Everyday professional and knowledge work: Claude Sonnet 5 — A core design strength of Claude Sonnet 5.
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.
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 Sonnet 5, and on millions of tokens that margin decides the monthly bill.
Anyone whose priority is agentic workflows that plan, use tools, and run autonomously: Claude Sonnet 5 — It is specifically built for that.
Anyone whose priority is strong general-purpose default: GPT-5.4 — That is its strongest area.
Claude Sonnet 5: where it fits
Anthropic's most agentic Sonnet, with near-Opus-4.8 performance at Sonnet prices; the default model on Free and Pro. Released June 30, 2026 by Anthropic, it is built for agentic workflows that plan, use tools, and run autonomously, multi-step coding, debugging, and tool use, everyday professional and knowledge work, and long-document analysis and reasoning.
Its trade-offs are real: lower peak accuracy than Opus 4.8 on the hardest tasks, and an updated tokenizer that can use 1.0-1.35x more tokens for the same text. At $3 in / $15 out per million tokens, it sits in the mid 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 Sonnet 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 Sonnet 5 for agentic workflows that plan, use tools, and run autonomously, 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.
Frequently asked questions
Is Claude Sonnet 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 Sonnet 5 leans toward agentic workflows that plan, use tools, and run autonomously 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 Sonnet 5 or GPT-5.4?
GPT-5.4 is cheaper — $3/$15 per 1M tokens vs $2.5/$15 per 1M tokens, roughly 1.2× 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 Sonnet 5 and GPT-5.4 together?
Yes — a multi-model platform like LumiChats gives you Claude Sonnet 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 Sonnet 5 or GPT-5.4?
Claude Sonnet 5 — released June 30, 2026, about 4 months after GPT-5.4.
Claude Sonnet 5 vs GPT-5.4
Anthropic · US | OpenAI · US · Updated June 2026
Quick verdict
Pick Claude Sonnet 5 for agentic workflows that plan, use tools, and run autonomously or multi-step coding, debugging, and tool use. 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 Sonnet 5 (Anthropic) and GPT-5.4 (OpenAI) are two of the models people most often weigh against each other in 2026. Claude Sonnet 5 is anthropic's most agentic Sonnet, with near-Opus-4.8 performance at Sonnet prices; the default model on Free and Pro. 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
▸Price: nearly identical — $3/$15 per 1M tokens vs $2.5/$15 per 1M tokens. Cost will not be the deciding factor here.
▸Context window: both advertise 1M (~1,500 pages). Tie on paper — test on your own long inputs, since usable recall varies by model.
▸Recency: Claude Sonnet 5 is the newer model by about 4 months (released June 30, 2026), usually meaning fresher training data and capabilities.
Side-by-side specs
Spec
Claude Sonnet 5
GPT-5.4
Provider
Anthropic (US)
OpenAI (US)
Released
June 30, 2026
March 5, 2026
Context window
1M (~1,500 pages)
1M (~1,500 pages)
Price (in/out)
$3/$15 per 1M tokens
$2.5/$15 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
Agentic workflows that plan, use tools, and run autonomously
Claude Sonnet 5
A core design strength of Claude Sonnet 5.
Multi-step coding, debugging, and tool use
Claude Sonnet 5
A core design strength of Claude Sonnet 5.
Everyday professional and knowledge work
Claude Sonnet 5
A core design strength of Claude Sonnet 5.
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.
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 Sonnet 5, and on millions of tokens that margin decides the monthly bill.
Anyone whose priority is agentic workflows that plan, use tools, and run autonomously
→ Claude Sonnet 5
It is specifically built for that.
Anyone whose priority is strong general-purpose default
→ GPT-5.4
That is its strongest area.
Claude Sonnet 5: where it fits
Anthropic's most agentic Sonnet, with near-Opus-4.8 performance at Sonnet prices; the default model on Free and Pro. Released June 30, 2026 by Anthropic, it is built for agentic workflows that plan, use tools, and run autonomously, multi-step coding, debugging, and tool use, everyday professional and knowledge work, and long-document analysis and reasoning.
Its trade-offs are real: lower peak accuracy than Opus 4.8 on the hardest tasks, and an updated tokenizer that can use 1.0-1.35x more tokens for the same text. At $3 in / $15 out per million tokens, it sits in the mid 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 Sonnet 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 Sonnet 5 for agentic workflows that plan, use tools, and run autonomously, 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 Sonnet 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.
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 Sonnet 5 leans toward agentic workflows that plan, use tools, and run autonomously 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 Sonnet 5 or GPT-5.4?
GPT-5.4 is cheaper — $3/$15 per 1M tokens vs $2.5/$15 per 1M tokens, roughly 1.2× 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 Sonnet 5 and GPT-5.4 together?
Yes — a multi-model platform like LumiChats gives you Claude Sonnet 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 Sonnet 5 or GPT-5.4?
Claude Sonnet 5 — released June 30, 2026, about 4 months after GPT-5.4.
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.