Compare Claude Opus 4.8 from Anthropic and gpt-oss-20b from OpenAI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
Claude Opus 4.8
gpt-oss-20bClaude Opus 4.8 is Anthropic’s newest and most powerful publicly available model. It is suitable for the most complex tasks. It is Anthropic’s strongest model for complex reasoning, long-horizon agent programming, and highly autonomous work.claude-opus-4-8 does not display thought content by default; you need to set the additional parameter "display": "summarized" to enable it
gpt-oss-20b is a 21-billion parameter open-weight model released by OpenAI under the Apache 2.0 license. Its core feature is a Mixture-of-Experts (MoE) architecture that uses only 3.6B active parameters, enabling low-latency inference and deployment on consumer GPUs. The model also supports fine-tuning, function calling, tool use, and structured outputs.
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Promotional prices show the discounted rate; see each model page for promotion windows.
Daily traffic served through AIHubMix — how demand for each model is trending.
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.
Source: LMArena (arena.ai) leaderboard, imported by AIHubMix. Models without published ratings are omitted per chart.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
gpt-oss-20b: $0.55/M output tokens; Claude Opus 4.8: $25/M. Use the cost calculator above to estimate your own workload.
Claude Opus 4.8: 1527; gpt-oss-20b: 1369 (LMArena coding leaderboard).
gpt-oss-20b: 0.1s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
Claude Opus 4.8 accepts 1,000,000 and gpt-oss-20b accepts 128,000 input tokens. Maximum output per request is 128,000 tokens on Claude Opus 4.8 and 32,768 tokens on gpt-oss-20b.
gpt-oss-20b at 2619.0 tok/s and Claude Opus 4.8 at 82.6 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
Claude Opus 4.8 accepts text, image and PDF input and supports thinking, tool calling, function calling and structured outputs; gpt-oss-20b accepts text input and supports thinking, function calling and structured outputs.
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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