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Gemini 4 Hydrogen vs Claude Sonnet 5.5
Claude Sonnet 5.5 scores higher than Gemini 4 Hydrogen on 3 of the 4 public leaderboards that rate both; the other one is tied. On the ArtificialWatch Index, which takes the median of each model's percentile across the boards that score it, Gemini 4 Hydrogen is at 81.9 and Claude Sonnet 5.5 at 83.3 (out of 100). On each maker's API, Gemini 4 Hydrogen costs $1.50 / $7.50 per 1M tokens (input / output) and Claude Sonnet 5.5 $2 / $10.
Scores as published by each board; table composed November 13, 2026.
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Leaderboard by leaderboard
| Board | Gemini 4 Hydrogen | Claude Sonnet 5.5 | Higher |
|---|---|---|---|
| LMArena Elo (community votes) | 1,704.2 | 1,772.3 | Claude Sonnet 5.5 |
| LiveBench global average (0-100) | 77 | 77 | tie |
| Vals AI Vals Index accuracy % · weighted finance + coding tasks | 68.5 | 70.9 | Claude Sonnet 5.5 |
| Artificial Analysis intelligence index · measured runs only | 53.9 | 54.5 | Claude Sonnet 5.5 |
Raw scores are each board's own scale, so compare within a row, not across rows. Full table: the bench index.
For coding
On the ArtificialWatch coding index, Gemini 4 Hydrogen is at 76 (#10 of 48) and Claude Sonnet 5.5 at 65.1 (#16). Gemini 4 Hydrogen scores higher on 2 of the 3 coding boards that rate both and Claude Sonnet 5.5 on 1.
| Coding board | Gemini 4 Hydrogen | Claude Sonnet 5.5 |
|---|---|---|
| LMArena · Coding | 1,515.9 | 1,500.9 |
| LiveBench · Coding | 78.5 | 77.2 |
| Vals Vibe Code Bench | 87.8 | 92.4 |
Gemini 4 Hydrogen at a glance
- Developer
- Status
- Live since November 12, 2026
- API price
- $1.50 input / $7.50 output per 1M tokens · Google, gemini-4-hydrogen
- Context window
- 1.05M tokens
Live — Nov 12 · GA on the Gemini API as gemini-4-hydrogen (Google's release notes, Nov 12), free tier and paid tier, also in Google AI Studio and the default model for the Antigravity agent in Gemini Managed Agents · $1.50 / $7.50 per 1M, $0.075 cached (implicit caching only); Batch and Flex $0.75 / $3.75; Priority $2.70 / $13.50 · no introductory discount: the same as the SKU rows Google Cloud listed at 08:50 UTC · 1M unified context; 65,536 max output by default, up to 1M with long decode · text, image, video, audio and PDF in, text out · thinking levels low, medium, high (default) and a new xhigh · Google calls Gemini 3.8 Flash its 'previous-generation Flash model' ($0.75 / $3.75 intro through Dec 31, $1.50 / $7.50 from Jan 1) · our sweep fired at 17:46 UTC · before launch: codename reported since Oct 27, Business Insider (Nov 11) on staff testing, billing SKUs Nov 12 08:50 UTC · Nov 12 18:50 UTC: 54 on Artificial Analysis' Intelligence Index (Gemini 4 Hydrogen (Xhigh)), above Gemini 4 Argon (50) and GPT-6.1 Terra (51), one point under Claude Sonnet 5.5 (55); 54.3% on CursorBench at High, 12th of its listed settings.
Gemini 4 Hydrogen is live: Google's new everyday model costs $1.50 / $7.50 per 1M tokens, with a free tier and a 1M context
2026-11-12 · Google released Gemini 4 Hydrogen (gemini-4-hydrogen) on November 12 as generally available on the Gemini API, on the free tier and at $1.50 per 1M input tokens and $7.50 per 1M output tokens on the paid tier.
Gemini 4 Hydrogen appears in Google Cloud's price list at $1.50 input and $7.50 output per 1M tokens, before Google has announced it
2026-11-12 · Google Cloud's public SKU list now carries Gemini 4 Hydrogen under two services, the Gemini API and Vertex AI, before Google has announced the model. @Mr_Salio flagged the rows at 08:11 UTC on November 12, and ArtificialWatch read them on Google's SKU list at 08:50 UTC.
Claude Sonnet 5.5 at a glance
- Developer
- Anthropic
- Status
- Live since September 28, 2026
- API price
- $2 input / $10 output per 1M tokens · Anthropic, claude-sonnet-5-5
- Context window
- 1M tokens
Live — Sep 28 · $2/$10 per MTok, the same as Sonnet 5 · cache reads $0.20 at launch, halved to $0.10 on Oct 7, writes $2.50 · in the API, the Claude apps, AWS, Google Cloud and Azure the same day · 1M ctx / 128K out · knowledge cutoff Jun 2026 · Artificial Analysis Intelligence Index 56 at max effort, #3 of 216 reasoning models (read Sep 28) · Anthropic's own table: Terminal-Bench 4.0 70.6% (Opus 5.5 66.4%), OSWorld 2.1 80.1% (Opus 5.5 81.8%) · our sweep caught claude-sonnet-5-5 at 17:54 UTC and fired at 17:55.
Claude Sonnet 5.5 ships at Sonnet 5's price, and the first independent number puts it #3 among reasoning models
2026-09-28 · Claude Sonnet 5.5 is live. Our sweep read the id claude-sonnet-5-5 at 17:54:45 UTC on September 28 and the alert went out at 17:55:45, 60 seconds later, to 314 inboxes and one phone. OpenRouter listed it nine minutes after that.
Claude Sonnet 5.5: named by Anthropic, reportedly in partner testing, priced 89% by Sep 30
2026-09-27 · Anthropic has named Claude Sonnet 5.5 but has not dated it. Everything past the name is reported, not confirmed - and the one number that moves every day says it is close.
Gemini 4 Hydrogen vs Claude Sonnet 5.5: quick answers
Which is better, Gemini 4 Hydrogen or Claude Sonnet 5.5?
It depends on what you measure. Claude Sonnet 5.5 scores higher than Gemini 4 Hydrogen on 3 of the 4 public leaderboards that rate both; the other one is tied. Claude Sonnet 5.5's widest lead is on Vals AI. On the ArtificialWatch Index, which takes the median of each model's percentile across the boards that score it, Gemini 4 Hydrogen is at 81.9 and Claude Sonnet 5.5 at 83.3 (out of 100).
Which is newer, Gemini 4 Hydrogen or Claude Sonnet 5.5?
Gemini 4 Hydrogen. It went live on November 12, 2026, 45 days after Claude Sonnet 5.5 (September 28, 2026).
Which is cheaper, Gemini 4 Hydrogen or Claude Sonnet 5.5?
Gemini 4 Hydrogen is cheaper on both input and output. On each vendor's own API, Gemini 4 Hydrogen is $1.50 input / $7.50 output per million tokens and Claude Sonnet 5.5 is $2 input / $10 output per million tokens. Prices as published in the models.dev catalog, as of 2026-11-12.
Which has the bigger context window, Gemini 4 Hydrogen or Claude Sonnet 5.5?
Gemini 4 Hydrogen, at 1.05M tokens against Claude Sonnet 5.5's 1M, as each vendor lists it.
How do Gemini 4 Hydrogen and Claude Sonnet 5.5 compare for coding?
On the ArtificialWatch coding index, Gemini 4 Hydrogen is at 76 (#10 of 48) and Claude Sonnet 5.5 at 65.1 (#16). Gemini 4 Hydrogen scores higher on 2 of the 3 coding boards that rate both and Claude Sonnet 5.5 on 1.
Who makes Gemini 4 Hydrogen and Claude Sonnet 5.5?
Gemini 4 Hydrogen is from Google; Claude Sonnet 5.5 is from Anthropic.
Where do these numbers come from?
Each score is the leaderboard's own published figure, read by ArtificialWatch (table composed November 13, 2026). Boards measure different things, so raw scores are only comparable within a row.
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Also: the bench index · API pricing · what a workload costs on each · the wire