gpt-oss-120b API Pricing
OpenAI · context window 131K · prices updated 2026-10-30
Where gpt-oss-120b sits on price
At $0.6 per million output tokens, gpt-oss-120b is a mid tier model — 3.7× cheaper than the median output price of $2.20, which puts it cheaper than 78% and pricier than 22% of the models we track. It sits 14th cheapest of the 98 OpenAI models we track. Output costs 4.0× input, the usual spread — trim both, starting with the answer length.
Cached input is 50% cheaper. On an input-heavy workload you need roughly a 50% 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-oss-120b
These three workloads are the ones teams actually run on a mid-priced model — a $0.6/1M 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. | $0.0016 | $23.85 |
| Document pipeline — 10K docs/day (3K in / 500 out) Batch-friendly: no user waiting, so a ~50% batch discount usually applies. | $0.0008 | $225 |
| Small app — 1K requests/day (500 in / 150 out) The baseline most side projects actually run at. | $0.0002 | $4.95 |
Model your exact traffic in the API cost calculator — it preloads gpt-oss-120b with caching and batch options.
gpt-oss-120b price history
OpenAI last raised gpt-oss-120b's output price on Oct 15, 2026 (+253% per output token), from $0.037/$0.17 to $0.15/$0.6 per 1M in/out. That is one of 7 repricings in the 89 days we have tracked it — worth knowing before you hard-code today's rate into a budget.
| Date | Input /1M | Output /1M | Output change |
|---|---|---|---|
| Aug 2, 2026 (tracking began) | $0.037 | $0.17 | — |
| Aug 12, 2026 | $0.03 | $0.17 | 0% |
| Aug 23, 2026 | $0.037 | $0.17 | 0% |
| Sep 18, 2026 | $0.15 | $0.6 | +253% |
| Sep 29, 2026 | $0.037 | $0.17 | -72% |
| Oct 13, 2026 | $0.15 | $0.6 | +253% |
| Oct 14, 2026 | $0.037 | $0.17 | -72% |
| Oct 15, 2026 | $0.15 | $0.6 | +253% |
Change-points from our daily price snapshots (tracking since Aug 2, 2026; intraday moves between snapshots are not captured).
gpt-oss-120b vs Qwen3 VL 30B A3B Instruct
The closest-priced alternative from another vendor is Qwen3 VL 30B A3B Instruct (Alibaba (Qwen)) — priced within a rounding error 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 Qwen3 VL 30B A3B Instruct pricing →Cheaper alternatives
More OpenAI models
Frequently asked questions
› How much does the gpt-oss-120b API cost?
gpt-oss-120b costs $0.15 per million input tokens and $0.6 per million output tokens, with cached input at $0.075 per million (50% cheaper). That works out to roughly 1,666,667 output tokens per dollar.
› What does the support chatbot workload cost on gpt-oss-120b?
Support chatbot — 500 conversations/day (5K in / 1.4K out) costs about $0.0016 per request and $23.85 per month on gpt-oss-120b. Conversation history re-sent each turn — the classic prompt-caching win.
› What does it cost to fill gpt-oss-120b's 131K context window?
Sending 131K of input in a single request costs $0.0197 at $0.15 per million tokens — before any output. With prompt caching that same fill drops to about $0.0098 on repeat requests. This is why large context windows are cheap to advertise and expensive to actually use.
› Is gpt-oss-120b worth the price?
gpt-oss-120b sits in the middle of the market (14 of 98 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.