gpt-oss-120b Open vs GPT-4o-mini Paid
gpt-oss-120b vs GPT-4o-mini compared — price per token, context window, multimodality, openness and which to choose. Can the open-source model replace the paid one? Full 2026 breakdown.
Prices & specs refreshed from live data · OpenSourceAI.tech
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
gpt-oss-120b vs GPT-4o-mini specs
| Spec | gpt-oss-120b | GPT-4o-mini |
|---|---|---|
| Maker | OpenAI | OpenAI |
| Type | Open-weight | Proprietary |
| Context window | 131K tokens | 128K tokens |
| Input price | $0.04/M · free self-host | $0.15/M |
| Output price | $0.17/M · free self-host | $0.6/M |
| Vision / multimodal | No | Yes |
| Tool / function calling | Yes | Yes |
| Self-hostable | Yes | No (API only) |
| License | Apache 2.0 | Proprietary |
Feature comparison
| Capability | gpt-oss-120b | GPT-4o-mini |
|---|---|---|
| Open weights (downloadable) | ✓ | ✗ |
| Self-hostable | ✓ | ✗ |
| Runs fully offline | ✓ | ✗ |
| Vision / multimodal | ✗ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✗ | ✗ |
Benchmarks: gpt-oss-120b vs GPT-4o-mini
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How gpt-oss-120b and GPT-4o-mini score
| Criterion | gpt-oss-120b | GPT-4o-mini |
|---|---|---|
| Cost-efficiency | 5.0 | 5.0 |
| Context window | 3.5 | 3.5 |
| Openness | 5.0 | 1.5 |
| Self-hosting | 5.0 | 1.0 |
| Multimodality | 3.5 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
gpt-oss-120b Open
gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI designed for high-reasoning, agentic, and general-purpose production use cases. It activates 5.1B parameters per forward pass and is optimize
GPT-4o-mini Paid
GPT-4o mini is OpenAI's newest model after [GPT-4 Omni](/models/openai/gpt-4o), supporting both text and image inputs with text outputs. As their most advanced small model, it is many multiples more affordable...
Other models in these families
These variants are tracked but not compared here — one page per family keeps the comparison readable.
Frequently asked questions
Is gpt-oss-120b as good as GPT-4o-mini?
gpt-oss-120b is open-weight and competitive on many tasks, but GPT-4o-mini may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.
Can I run gpt-oss-120b locally?
Yes. gpt-oss-120b has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. GPT-4o-mini is API-only and cannot be self-hosted.
How much cheaper is gpt-oss-120b?
gpt-oss-120b costs $0.17/M output vs $0.6/M for GPT-4o-mini — roughly 4x cheaper via API, and free if you self-host.
gpt-oss-120b vs GPT-4o-mini — which should I pick in 2026?
Choose gpt-oss-120b if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose GPT-4o-mini if you want frontier capability through a managed API with zero infrastructure to run.
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