o3 API Pricing
OpenAI · context window 200K · prices updated 2026-09-15
Where o3 sits on price
At $8.00 per million output tokens, o3 is a premium tier model — 3.8× the median output price of $2.08, which puts it cheaper than 23% and pricier than 77% of the models we track. It sits 50th cheapest of the 92 OpenAI models we track. Output costs 4.0× input, the usual spread — trim both, starting with the answer length.
Cached input is 75% cheaper. On an input-heavy workload you need roughly a 33% 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 o3
These three workloads are the ones teams actually run on a premium-priced model — a $8.00/1M model is not bought for the same job as one ten times the price.
| Workload | Per request | Per month |
|---|---|---|
| Support chatbot — 500 conversations/day (5K in / 1.4K out) Conversation history re-sent each turn — the classic prompt-caching win. | $0.0212 | $318 |
| Coding agent — 300 sessions/day (60K in / 12K out) Multi-step loops re-read the same files; caching matters more than raw price. | $0.216 | $1944 |
| Small app — 1K requests/day (500 in / 150 out) The baseline most side projects actually run at. | $0.0022 | $66.00 |
Model your exact traffic in the API cost calculator — it preloads o3 with caching and batch options.
o3 price history
o3'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).
o3 vs Claude Sonnet 4.6 (batch)
The closest-priced alternative from another vendor is Claude Sonnet 4.6 (batch) (Anthropic) — 6% cheaper on output, with $0.5 less per million input tokens. 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 Sonnet 4.6 (batch) pricing →Cheaper alternatives
More OpenAI models
Frequently asked questions
› How much does the o3 API cost?
o3 costs $2.00 per million input tokens and $8.00 per million output tokens, with cached input at $0.5 per million (75% cheaper). That works out to roughly 125,000 output tokens per dollar.
› What does the support chatbot workload cost on o3?
Support chatbot — 500 conversations/day (5K in / 1.4K out) costs about $0.0212 per request and $318 per month on o3. Conversation history re-sent each turn — the classic prompt-caching win.
› What does it cost to fill o3's 200K context window?
Sending 200K of input in a single request costs $0.4 at $2.00 per million tokens — before any output. With prompt caching that same fill drops to about $0.1 on repeat requests. This is why large context windows are cheap to advertise and expensive to actually use.
› Is o3 worth the price?
o3 sits in the middle of the market (50 of 92 by price within OpenAI). The honest test is a routing experiment: send the same 200 real requests to this model and to a tier below, and compare failure rate against the price gap — most teams find a majority of traffic never needed the pricier model.