Compare DeepSeek V4 Flash from DeepSeek 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.
DeepSeek V4 Flash
gpt-oss-20b(This model currently points to the older 0423 version; if you need to request the latest version, you can choose the model deepseek-v4-flash-0731)DeepSeek-V4 features an ultra-long context of one million characters and achieves leading performance domestically and in the open-source domain in agent capabilities, world knowledge, and reasoning.
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.
DeepSeek V4 Flash: $0.284/M output tokens; gpt-oss-20b: $0.55/M. Use the cost calculator above to estimate your own workload.
DeepSeek V4 Flash: 1483; 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.
DeepSeek V4 Flash accepts 1,000,000 and gpt-oss-20b accepts 128,000 input tokens. Maximum output per request is 384,000 tokens on DeepSeek V4 Flash and 32,768 tokens on gpt-oss-20b.
gpt-oss-20b at 2619.0 tok/s and DeepSeek V4 Flash at 66.5 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
DeepSeek V4 Flash accepts text input and supports tool calling, function calling, structured outputs and thinking; 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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