GPT-5.5 vs GPT-5.4: Which Should You Use? (2026)

As of June 2026, GPT-5.5 is $5.00 input / $30.00 output per million tokens, and GPT-5.4 is $2.50 / $15.00 — exactly half on both sides. The output gap is the one to watch: $30 vs $15 means a long-output workload on GPT-5.5 costs twice as much per generated token.

Below the flagships, the GPT-5.4 family gets much cheaper: gpt-5.4-mini at $0.75 / $4.50 and gpt-5.4-nano at $0.20 / $1.25. There's also a coding-focused gpt-5.3-codex at $1.75 / $14.00. All figures are on the OpenAI pricing page — always check the live page, since prices move.

The practical takeaway: the GPT-5 line spans a wide cost range, and most teams overspend by running everything on the top tier. Match the tier to the difficulty of the task.

GPT-5.5 is OpenAI's most capable GPT-5 model, and the gap shows up most on hard problems: dense reasoning, complex multi-step coding, ambiguous tasks where weaker models confidently go wrong, and long agentic chains where errors compound.

A good rule of thumb: if you're re-running GPT-5.4 several times to fix the same class of mistake, the retries (in both time and tokens) often cost more than just using GPT-5.5 once. Reserve the flagship for the requests that actually need it.

GPT-5.5 is also the safer choice for high-stakes, one-shot outputs — anything where a subtle error is expensive to catch downstream. For everything else, GPT-5.4 is usually plenty.

Reach for GPT-5.5 when: the task is hard reasoning, complex coding, long agentic work, or a high-stakes one-shot output where capability matters more than cost.
Stick with GPT-5.4 when: you're doing drafting, summarization, classification, standard code, chat, or anything at volume where the cost savings outweigh the small capability gap.

GPT-5.4 is the right default for most production and everyday work. At half the price of GPT-5.5, it covers content drafting, summarization, extraction, classification, customer chat, and the bulk of code generation with quality most teams won't be able to distinguish from the flagship on routine tasks.

For high-volume pipelines, drop further: gpt-5.4-mini ($0.75/$4.50) handles simpler classification, routing, and short generations at a fraction of the cost, and gpt-5.4-nano ($0.20/$1.25) is built for the cheapest, highest-throughput jobs like tagging or simple extraction. Use the smallest tier that passes your quality bar.

If your workload is mostly marketing or support content, GPT-5.4 will serve you well — pair it with our ad copy generator or social media caption tool prompts.

The cost-effective pattern is a ladder: route simple, high-volume tasks to nano or mini, run general work on GPT-5.4, and escalate to GPT-5.5 only when a task is flagged hard or high-stakes — or when GPT-5.4's output fails a quality check.

This keeps your average cost near the cheaper tiers while still getting flagship quality on the requests that need it. For prompt design tips that apply across the whole line, see OpenAI's prompt engineering guide.