Google's Gemini 4 Hydrogen costs double Flash, for now

Google's new workhorse is faster. For the next seven weeks it is also the expensive option.

Google released Gemini 4 Hydrogen on Nov. 12 and called it "our daily driver for agentic workflows." It is in the Gemini API, Google AI Studio, Android Studio, Gemini for business and the Gemini app. Google also says Hydrogen is now available in Google Search for all users globally.

The price, per Google's pricing page:

$1.50 per million input tokens. $7.50 per million output tokens.

Hydrogen replaces Flash at Flash's January price

Google measures Hydrogen against Gemini 3.8 Flash. It says Hydrogen finishes tasks 2.5 times faster than 3.8 Flash at the default thinking level, and that partners measured 2x to 2.8x faster runs with 12% to 23% fewer tokens.

The pricing page tells the rest. Gemini 3.8 Flash costs $0.75 input and $3.75 output through Dec. 31. On Jan. 1 it rises to $1.50 and $7.50.

That is exactly Hydrogen's price.

So today Hydrogen costs twice as much per token as the model it replaces. In seven weeks it costs the same.

Here's the thing: fewer tokens close only part of that gap. A task that uses 20% fewer tokens at double the rate still costs you 60% more. Speed is worth money only if your users or your pipeline are waiting on it.

Google's benchmarks are strong, and they are Google's

Google reports Hydrogen scores 51 on the Artificial Analysis Intelligence Index at its default setting, above the 50 it lists for the larger Gemini 4 Argon, and 54 at a new xhigh level. On Terminal-Bench 4.1, Google puts Hydrogen at 57% against 18.2% for 3.8 Flash.

Google also says Hydrogen is more than 2.3 times more resilient to indirect prompt injection on the Gray Swan benchmark.

These are the company's numbers, on the company's settings. Read them as claims until outside leaderboards catch up.

The context window is 1 million tokens, priced flat across the whole window, and output can run to 1 million tokens, Google says. There are four reasoning effort levels: low, medium, high (the default) and the new xhigh.

In its Antigravity coding tool, a new Orchestrator feature pairs Hydrogen with Gemini 4 Carbon, per Google's developer post. TopFive covered Carbon's API launch on Nov. 11.

In Search, Google's Robby Stein calls this "the biggest model upgrade to Search yet." Google says Search now handles longer, multi-part questions and links to a wider range of sites. It gave no numbers.

Test it on your work before Dec. 31

If you run agents on 3.8 Flash, run Hydrogen on a week of your real tasks now. Log tokens per task, time to finish and how often a person has to fix the result.

That gives you the number Google's chart cannot: your cost per finished task.

If Hydrogen wins on that number, switch in January at no extra cost. If it only wins on speed, decide whether speed is worth double until then.

Free users of the Gemini app get Hydrogen only when automatic model selection picks it, Google says. The Gemini API's free tier lists it as free of charge.

Watch the Flash price on Jan. 1

Two things decide this. Whether Google extends the 3.8 Flash discount past Dec. 31, and whether independent benchmarks land near Google's own.

Test now. Switch on your numbers.