Released 56 days after O3 Pro · All OpenAI releases
GPT-OSS 20B is an open-weight Mixture-of-Experts language model released by OpenAI in August 2025 under the Apache 2.0 license, alongside the larger 120B variant. It has 20.9B total parameters with 3.6B active per token across 24 layers, and can run on devices with around 16GB of memory. The model matches or exceeds OpenAI o3-mini on common benchmarks while staying highly efficient. It supports reasoning, tool use with function calling, and structured outputs, fitting cost-conscious agentic workflows and local inference. Its MoE design selects the top 4 of 32 experts per token, with a 128k context window, giving developers a compact open-weight option that keeps strong reasoning capability.
GPT OSS 20B runs on 8 different routes through the Opper gateway. Compare residency, ZDR, and training posture at a glance — full data-handling detail per route below.
| Provider | Region | Zero data retention | Training | Input | Output |
|---|---|---|---|---|---|
| EU | Zero data retention | No | $0.07 | $0.30 | |
| US | Not by default | No | $0.05 | $0.45 | |
| Multi | Zero data retention | No | $0.07 | $0.30 | |
| EU/EEA | Zero data retention | No | $0.03 | $0.14 | |
| US | Zero data retention | No | $0.03 | $0.14 | |
| US | Not by default | No | $0.07 | $0.30 | |
| US | Zero data retention | No | $0.04 | $0.15 | |
| EU | Zero data retention | No | $0.12 | $0.49 |
GPT OSS 20B runs on 4 independently monitored routes through the Opper gateway. A direct integration leaves you on one of them, the gateway serves whichever is healthy.
Measured over the last 30 days from each provider's official status feed via StatusGator. Refreshed hourly. 3 further routes for this model are not on the board yet and are not counted above. See uptime for every provider Opper monitors.
Each route hosting GPT OSS 20B has its own privacy posture, residency, and GDPR terms. Postures are maintained by Opper with a last-verification timestamp.
Zero data retention is on by default on Pay-as-you-go — no action required. No training on customer data. EU; DPA available.
Zero data retention is not on by default — a moderation hold applies. No training on customer data. US; dpf sccs; DPA available.
Zero data retention is on by default on Pay-as-you-go — no action required. No training on customer data. GLOBAL; SCCs; DPA available.
Zero data retention is on by default on Pay-as-you-go — no action required. No training on customer data. EEA; SCCs; DPA available.
Zero data retention is on by default on Pay-as-you-go — no action required. No training on customer data. US; SCCs; DPA available.
Zero data retention is not on by default — abuse monitoring, 30-day retention. No training on customer data. US; SCCs; DPA available.
Zero data retention is on by default on Pay-as-you-go — no action required. No training on customer data. US; SCCs; DPA available.
Zero data retention is on by default on Pay-as-you-go — no action required. No training on customer data. EU; DPA available.
Independent benchmark scores — composite indices for reasoning, coding, and math, plus individual eval scores where available.
Call GPT OSS 20B through the Opper gateway with one API key. Let your coding agent set it up, or call it directly — Opper is drop-in compatible with the OpenAI, Anthropic, and Google AI SDKs.
Copy this and paste it into a coding agent like Claude Code, Cursor or Codex and it'll wire up Opper for you.
import OpenAI from "openai";const client = new OpenAI({apiKey: process.env.OPPER_API_KEY,baseURL: "https://api.opper.ai/v3/compat",});const completion = await client.chat.completions.create({model: "aws/gpt-oss-20b-eu",messages: [{ role: "user", content: "Hello" }],});console.log(completion.choices[0].message.content);
Side-by-side on privacy, EU hosting, pricing, and benchmarks.
