Compare / Models
Claude Sonnet 5.5 vs Gemini 4 Hydrogen
Price, context window and capabilities side by side, read from the same catalog that meters your calls, not from a press release.
Gemini 4 Hydrogen is 1.3x cheaper on input. Gemini 4 Hydrogen is 1.3x cheaper on output. Gemini 4 Hydrogen holds 1M tokens against 1M.
At a glance
Side by side
Anthropic
The fast Claude 5.5: near-Opus coding and knowledge work, 30%+ faster than Sonnet 5, at half Opus 5.5's price.
Google DeepMind's fast, efficient Gemini 4 model for everyday coding and agentic work: four thinking levels and a 1M-token window at one flat price.
Specifications
Every difference we can measure
| Claude Sonnet 5.5 | Gemini 4 Hydrogen | |
|---|---|---|
| Input price | $2/M | $1.5/M |
| Output price | $10/M | $7.5/M |
| Context window | 1M tokens | 1M tokens |
| Vision | Yes | Yes |
| Tool calling | Yes | Yes |
| Prompt caching | No | Yes |
| Long context | Yes | Yes |
A row appears only when we hold the fact for both models. Anything the provider has not published is left out rather than guessed, so an empty row is missing data and never a zero.
Verdict
Which to pick
Claude Sonnet 5.5 is $2 / $10 per million tokens and Hydrogen is $1.50 / $7.50, a quarter cheaper per token, with a 1,048,576-token window against Sonnet's 1,000,000 and the price flat across all of it. Google reports Hydrogen matching or beating models in its class on coding and agent benchmarks; those are Google's numbers, not independent results. Run your own agent loop on both through one key and compare the answers and usage.cost_usd.
Keep looking
Related comparisons
FAQ
Frequently asked questions
What is the difference between Claude Sonnet 5.5 and Gemini 4 Hydrogen?
Gemini 4 Hydrogen is 1.3x cheaper on input. Gemini 4 Hydrogen is 1.3x cheaper on output. Gemini 4 Hydrogen holds 1M tokens against 1M. Only Gemini 4 Hydrogen declares prompt caching. Both run on the same endpoint and the same key here, so trying each is a one-line change to the model id.
Which is cheaper, Claude Sonnet 5.5 or Gemini 4 Hydrogen?
Gemini 4 Hydrogen is, on input tokens. Output usually dominates the bill on generative work, so check the output row above against your own ratio of prompt to completion before deciding.
Can I switch between Claude Sonnet 5.5 and Gemini 4 Hydrogen without changing my code?
Yes. Both are OpenAI-compatible through one CompanyFabric key, so switching is the model string and nothing else, no second SDK, no second contract, one prepaid balance across both.
Do I have to choose?
No. Send companyfabric/auto and we route each request to the cheapest model that can serve it, which is how most people use both without deciding in advance.
One key. Every model. Exact prices.
Run Claude Sonnet 5.5 and Gemini 4 Hydrogen on the same key and compare them on your own prompts. Free starter credits included, no subscription required.