GPT-5.5 API Pricing
OpenAI · context window 1.1M · prices updated 2026-09-15
Where GPT-5.5 sits on price
At $30.00 per million output tokens, GPT-5.5 is a frontier tier model — 14.4× the median output price of $2.08, which puts it in the most expensive 10% of everything we track. It sits 78th cheapest of the 92 OpenAI models we track. Output costs 6.0× more than input here, so anything that makes the model write less — tighter instructions, structured output, lower max_tokens — moves the bill more than trimming the prompt.
Cached input is 90% cheaper. On an input-heavy workload you need roughly a 28% cache-hit rate to take 25% off the input line — reachable for chatbots and agents that resend the same system prompt and history.
What real workloads cost on GPT-5.5
These three workloads are the ones teams actually run on a frontier-priced model — a $30.00/1M model is not bought for the same job as one ten times the price.
| Workload | Per request | Per month |
|---|---|---|
| Small app — 1K requests/day (500 in / 150 out) The baseline most side projects actually run at. | $0.007 | $210 |
| Coding agent — 300 sessions/day (60K in / 12K out) Multi-step loops re-read the same files; caching matters more than raw price. | $0.66 | $5940 |
| Support chatbot — 500 conversations/day (5K in / 1.4K out) Conversation history re-sent each turn — the classic prompt-caching win. | $0.067 | $1005 |
Model your exact traffic in the API cost calculator — it preloads GPT-5.5 with caching and batch options.
GPT-5.5 price history
GPT-5.5's price has not moved since we began tracking it on Aug 2, 2026 — 44 days of stability in a market where 78 of the 334 models we track have repriced over the same period, including 9 of OpenAI's own 92 models.
Change-points from our daily price snapshots (tracking since Aug 2, 2026; intraday moves between snapshots are not captured).
GPT-5.5 vs Claude Fable 5.1 (batch)
The closest-priced alternative from another vendor is Claude Fable 5.1 (batch) (Anthropic) — 17% cheaper on output, with identical input pricing. When two models land this close on price, the decision is quality on your own workload, not the price sheet: run 50 real requests through both and compare.
See Claude Fable 5.1 (batch) pricing →Cheaper alternatives
More OpenAI models
Frequently asked questions
› How much does the GPT-5.5 API cost?
GPT-5.5 costs $5.00 per million input tokens and $30.00 per million output tokens, with cached input at $0.5 per million (90% cheaper). That works out to roughly 33,333 output tokens per dollar.
› What does the small app workload cost on GPT-5.5?
Small app — 1K requests/day (500 in / 150 out) costs about $0.007 per request and $210 per month on GPT-5.5. The baseline most side projects actually run at.
› What does it cost to fill GPT-5.5's 1.1M context window?
Sending 1.1M of input in a single request costs $5.25 at $5.00 per million tokens — before any output. With prompt caching that same fill drops to about $0.525 on repeat requests. This is why large context windows are cheap to advertise and expensive to actually use.
› Is GPT-5.5 worth the price?
GPT-5.5 is priced in the top bracket, at $30.00 per million output tokens. It only pays off where an error is expensive — production code, legal and medical drafting, agents that take real actions. For anything routine, Claude Fable 5.1 (batch) at $25.00 does the same job for a fraction of the bill.