Compare Gemini 3.8 Flash from Google and Gemini 4 Hydrogen from Google on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
Gemini 3.8 FlashGemini 4 HydrogenGemini 3.8 Flash is Google's most intelligent Flash-series model, designed for long-running software engineering tasks, autonomous agents, and complex enterprise workflows, while retaining the Flash series' fast responsiveness and cost-effectiveness.
Gemini 4 Hydrogen is a Google Gemini 4 model focused on speed and efficiency. Potential use cases include everyday conversations, text processing, and interactive applications where fast responses matter.
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.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
Gemini 3.8 Flash: $3.75/M output tokens; Gemini 4 Hydrogen: $7.5/M. Use the cost calculator above to estimate your own workload.
Gemini 4 Hydrogen: 4.2s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
Gemini 3.8 Flash accepts 1,048,576 and Gemini 4 Hydrogen accepts 1,048,576 input tokens. Maximum output per request is 65,536 tokens on Gemini 3.8 Flash and 65,536 tokens on Gemini 4 Hydrogen.
Gemini 4 Hydrogen at 115.9 tok/s and Gemini 3.8 Flash at 76.5 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
Gemini 3.8 Flash accepts text, image, video, audio and PDF input and supports thinking, tool calling, function calling, structured outputs, web search and long context; Gemini 4 Hydrogen accepts text, image, video, audio and PDF input.
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