The benchmark for AI assistants

GPT-5.4 is OpenAI's most capable model yet. With a 10 million token context window, native multimodal reasoning across text, images, audio, and video, and an agentic execution mode that can autonomously browse the web, fill forms, and run code — GPT-5.4 remains the model every other AI is measured against. The $20/mo Plus tier gives you most of what you need; the $200/mo Pro tier unlocks the full 10M context and unlimited agentic execution.

Who it's for: Everyone. GPT-5.4 is the best general-purpose AI assistant. Whether you're writing, coding, analyzing data, researching, or building AI products, this is the default choice.

Key features

10M Token Context

10 million token context window — entire codebases, book series, or research paper collections in a single conversation. No more chunking, no more forgetting earlier context. (Pro tier only.)

🔄 Native Multimodal

Text, images, audio, and video in one conversation. Upload a video, ask questions about specific frames, generate an image response, and get a voice summary — all in one thread.

🤖 Agentic Execution

Autonomously browse the web, click buttons, fill forms, and run code. GPT-5.4 can complete multi-step tasks — booking flights, researching competitors, building apps — with minimal supervision.

🎙️ Real-Time Voice

Sub-300ms latency voice mode that feels like talking to a human. Natural conversation flow, interruptions, emotional tone detection. The best AI voice experience available.

💻 Code Interpreter 2.0

Runs Python, R, and JavaScript with live output. Upload a CSV, ask for analysis, get charts and insights. Build and test code in real-time without leaving the chat.

🏪 Custom GPTs Marketplace

100,000+ specialized GPT assistants for every use case — legal analysis, medical research, coding helpers, creative writing. Or build your own with natural language.

The honest take

✓ What works

Best general-purpose AI model available — excels at everything
10M token context is unmatched by any competitor
Agentic mode actually works reliably for real tasks
Voice mode feels genuinely human with sub-300ms latency
Massive ecosystem of GPTs, plugins, and integrations

✗ What doesn't

$200/mo Pro is steep for the 10M context and unlimited agentic use
Can be overly cautious with certain content topics
Agentic mode uses credits fast — heavy users hit limits quickly
10M context only available on Pro tier — Plus is limited to 256K

Verdict

GPT-5.4 remains the benchmark for AI assistants in 2026. If you want the most capable all-around AI and don't mind paying for it, this is it. For most users, the $20/mo Plus tier is sufficient. Power users who need the 10M context and agentic execution should consider Pro.

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