GPT-5.4 wins on benchmarks. Opus wins on agentic tasks. Here's when to use each.
This is the matchup everyone asks about. OpenAI's GPT-5.4 and Anthropic's Claude Opus 4.6 are the two most talked-about AI models of 2026. GPT-5.4 leads on aggregate benchmarks. Opus 4.6 leads on real-world coding tasks and agentic workflows. The right choice depends entirely on what you're building.
On paper, GPT-5.4 wins clearly. Intelligence: 57.2 vs 53.0. Coding: 57.3 vs 48.1. Speed: 77 vs 51 tok/s. Price: $2.50/$15 vs $5/$25 per million tokens.
But benchmark scores don't tell the whole story. These composites aggregate many different tasks, and the weighting determines the ranking. On individual benchmarks, the picture is more nuanced.
GPT-5.4 excels at structured tasks with clear right answers. Competitive programming, math proofs, multiple-choice knowledge tests, formal logic — anything where precision matters and there's a definitive correct answer. Its FrontierMath score (50% on Tiers 1-3) is a record.
It's also better for high-volume API usage. At half the price and 51% more speed, the economics favor GPT-5.4 for applications processing millions of requests. Chatbots, customer support, content generation at scale — GPT-5.4 is the practical choice.
The 1.05M token context window is slightly larger than Opus's 1M, and GPT-5.4 maintains quality better at extreme context lengths in our testing.
Opus 4.6 dominates on tasks that require sustained focus and real-world judgment. SWE-bench Verified — where models must resolve actual GitHub issues in real codebases — is the marquee example. Opus scores 80.8%, ahead of Gemini 3.1 Pro at 80.6% and well ahead of GPT-5.4.
The difference is what 'coding' means. The AA Coding Index measures competitive programming and algorithmic problem-solving. SWE-bench measures the ability to understand a large codebase, locate the relevant files, understand the issue, and produce a working fix. These are fundamentally different skills.
Opus also leads on agentic tasks. Its METR-estimated task horizon of 14.5 hours means it can work autonomously on complex multi-step tasks without quality degradation. For Claude Code, Cursor, and similar AI coding assistants that need to make decisions over hundreds of steps, Opus is the clear choice.
Anthropically, Opus is also more cautious about code safety. It's more likely to flag security issues, avoid generating vulnerable code patterns, and ask clarifying questions when a task is ambiguous.
GPT-5.4 at $2.50/$15 is half the price of Opus at $5/$25. For a developer running 100K requests per month with average 1,000 input + 500 output tokens per request, that's roughly:
GPT-5.4: $250 input + $750 output = $1,000/month Opus 4.6: $500 input + $1,250 output = $1,750/month
The $750 monthly difference matters for startups and small teams. For enterprises where model quality directly impacts revenue (code quality, customer satisfaction), the premium for Opus may be justified.
Both models support prompt caching, which reduces the effective cost significantly for applications with repeated context.
There's no universal 'better' model here. The right choice depends on your use case:
Choose GPT-5.4 if: You need the highest benchmark scores, you're processing high volumes, you care about speed, you're doing competitive programming or math-heavy work, or you're building a chatbot.
Choose Claude Opus 4.6 if: You're building coding agents that work autonomously, you need sustained performance over long sessions, you're working on real-world software engineering (not puzzles), you value code safety and caution, or you're using Claude Code/Cursor.
Many teams use both: GPT-5.4 for high-volume, quick tasks and Opus 4.6 for complex, high-stakes coding work.
Head-to-head comparison using Artificial Analysis Intelligence and Coding indices, SWE-bench Verified scores (from Anthropic and OpenAI published results), speed measurements (AA median P50), and standard API pricing. Both models tested in default configuration.
GPT-5.4 wins on benchmarks, speed, and price. Claude Opus 4.6 wins on real-world coding, agentic tasks, and sustained quality. For most developers, GPT-5.4 is the default choice. For AI-assisted software engineering at scale, Opus 4.6 justifies its premium.
Published April 5, 2026. Data updated daily from independent benchmarks and API providers.