Claude Fable 5.2 vs Gemini 4 Hydrogen
Claude Fable 5.2 leads Gemini 4 Hydrogen on coding, 87.8 to 77.9 on the Vibe Coding Index, and Gemini 4 Hydrogen costs 5.3x less per output token ($7.50 vs $40.00 per million). Updated November 14, 2026; 26 benchmarks have a result for both.
Claude Fable 5.2 or Gemini 4 Hydrogen: which to pick
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 77.9 for Gemini 4 Hydrogen.
Pick Gemini 4 Hydrogen for output tokens 5.3x cheaper ($7.50 vs $40.00 per million) and a larger context window (1.05M against 1M tokens).
- Shared results
- 26
- Claude Fable 5.2 only
- 42
- Gemini 4 Hydrogen only
- 24
- Like-for-like categories
- 6 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
Claude Fable 5.2
Claude Fable 5.2 scores 87.8 against 77.9.
4 benchmarks behind each score
Intelligence
AA Intelligence Index
No call
Only Claude Fable 5.2 has a AA Intelligence Index result, 64.6.
Directional only
Web design
Design Arena: websites
Claude Fable 5.2
Claude Fable 5.2 leads, 1351 against 1320.
Same board, both measured
General
Vals Index
Claude Fable 5.2
Claude Fable 5.2 leads, 71.3% against 68.5%.
Same board, both measured
Long documents
Listed context window
Gemini 4 Hydrogen
Gemini 4 Hydrogen takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 4 Hydrogen
Claude Fable 5.2 $0.028, Gemini 4 Hydrogen $0.0053 per turn.
List prices
At a glance
- Coding index
- Claude Fable 5.2 87.8 from 4 benchmarks, Gemini 4 Hydrogen 77.9 from 4 benchmarks.
- Widest category
- Agentic work, 12.1 points apart on average over 6 shared benchmarks.
- Widest single gap
- HLE-Diamond (Artificial Analysis run): Claude Fable 5.2 80.2% against Gemini 4 Hydrogen 58.8%, 21.4 points apart on a 0 to 100 scale.
- Output price
- Claude Fable 5.2 $40.00 against Gemini 4 Hydrogen $7.50 per million output tokens, 5.3x apart.
- Context window
- Claude Fable 5.2 takes 1M tokens, Gemini 4 Hydrogen 1.05M.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Claude Fable 5.2 | Bars | Gemini 4 Hydrogen | Ties |
|---|---|---|---|---|
| Coding | 8 | 1 | ||
| Agentic work | 3 | 3 | ||
| Reasoning | 3 | 0 | ||
| Knowledge | 1 | 0 | ||
| Web design | 5 | 0 | ||
| General | 1 | 1 | ||
| All shared boards | 21 | 5 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index81
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| LiveBench coding | 79.2% | 78.5% | Claude Fable 5.2 |
| LMArena WebDev | 1838 | 1704 | Claude Fable 5.2 |
| Terminal-Bench 4 (Vals AI) | 65.2% | 54.0% | Claude Fable 5.2 |
| Vibe Code Bench (Vals AI) | 93.8% | 87.8% | Claude Fable 5.2 |
| ProgramBench (Vals AI) | 19.0% | Not measured | Only Claude Fable 5.2 measured |
| SWE-bench Multimodal (Vals AI) | 62.3% | Not measured | Only Claude Fable 5.2 measured |
| SciCode | 67.7% | Not measured | Only Claude Fable 5.2 measured |
| Terminal-Bench 4.0 (Artificial Analysis run) | 61.6% | 54.0% | Claude Fable 5.2 |
| FrontierCode 2.0 | 49.1% | 39.0% | Claude Fable 5.2 |
| FrontierSWE | 69.9% | Not measured | Only Claude Fable 5.2 measured |
| ALE-Bench | 2509.8 | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text: coding | Not measured | 1516 | Only Gemini 4 Hydrogen measured |
| LMArena Text: software and IT | Not measured | 1513 | Only Gemini 4 Hydrogen measured |
| LMArena WebDev: React | 1915 | 1724 | Claude Fable 5.2 |
| LMArena WebDev: HTML | 1738 | 1743 | Gemini 4 Hydrogen |
| GameBench 2 | 99.1 | Not measured | Only Claude Fable 5.2 measured |
| CursorBench 4.0 | 60.0% | 57.8% | Claude Fable 5.2 |
| Neither model has a result on the other 35 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| AA Intelligence Index | 64.6 | Not measured | Only Claude Fable 5.2 measured |
| Epoch Capabilities Index | 173.4 | Not measured | Only Claude Fable 5.2 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index33
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| Design Arena: agents building full-stack apps | 1402 | Not measured | Only Claude Fable 5.2 measured |
| Design Arena: agents building mobile apps | 1325 | Not measured | Only Claude Fable 5.2 measured |
| Design Arena: spreadsheets | 1434 | Not measured | Only Claude Fable 5.2 measured |
| LiveBench research | 94.5% | 86.8% | Claude Fable 5.2 |
| LiveBench browser | 86.9% | 77.1% | Claude Fable 5.2 |
| LiveBench long agentic | 82.9% | 61.8% | Claude Fable 5.2 |
| Tax Agent Bench (Vals AI) | 32.1% | 52.3% | Gemini 4 Hydrogen |
| Legal Research Bench (Vals AI) | 46.1% | 53.8% | Gemini 4 Hydrogen |
| Harvey's Legal Agent Benchmark (Vals AI) | 5.0% | 11.3% | Gemini 4 Hydrogen |
| BioMysteryBench (Vals AI) | 83.7% | Not measured | Only Claude Fable 5.2 measured |
| Terminal-Bench-Science (Vals AI) | 55.7% | Not measured | Only Claude Fable 5.2 measured |
| Vals Science Index | 63.7% | Not measured | Only Claude Fable 5.2 measured |
| APEX-Agents | 80.1% | Not measured | Only Claude Fable 5.2 measured |
| Remote Labor Index | 41.3% | Not measured | Only Claude Fable 5.2 measured |
| SpireClimb | 15.5% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 29 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| LiveBench reasoning | 88.8% | 88.6% | Claude Fable 5.2 |
| MysteryMechanism (Vals AI) | 51.8% | Not measured | Only Claude Fable 5.2 measured |
| Humanity's Last Exam (Artificial Analysis run) | 74.3% | Not measured | Only Claude Fable 5.2 measured |
| HLE-Diamond (Artificial Analysis run) | 80.2% | 58.8% | Claude Fable 5.2 |
| CritPt v2, hard subset (Artificial Analysis run) | 76.5% | 66.0% | Claude Fable 5.2 |
| GPQA Diamond (Epoch AI run) | 93.9% | Not measured | Only Claude Fable 5.2 measured |
| ARC-AGI | 98.5% | Not measured | Only Claude Fable 5.2 measured |
| ARC-AGI-2 | 93.8% | Not measured | Only Claude Fable 5.2 measured |
| SimpleBench | 94.9% | Not measured | Only Claude Fable 5.2 measured |
| Chess puzzles | 79.0% | Not measured | Only Claude Fable 5.2 measured |
| Mystery game puzzles | 90.0% | Not measured | Only Claude Fable 5.2 measured |
| EBR-bench | 90.5% | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text: hard prompts | Not measured | 1520 | Only Gemini 4 Hydrogen measured |
| LMArena Text: expert | Not measured | 1558 | Only Gemini 4 Hydrogen measured |
| LMArena Text: hard prompts in English | Not measured | 1514 | Only Gemini 4 Hydrogen measured |
| Humanity's Last Exam (Scale run) | 72.4% | Not measured | Only Claude Fable 5.2 measured |
| GoBench | 2566 | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 9 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| OTIS Mock AIME | 99.7% | Not measured | Only Claude Fable 5.2 measured |
| FrontierMath, tiers 1 to 3 | 95.1% | Not measured | Only Claude Fable 5.2 measured |
| FrontierMath, tier 4 | 100.0% | Not measured | Only Claude Fable 5.2 measured |
| ProofBench | 100.0% | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text: math | Not measured | 1507 | Only Gemini 4 Hydrogen measured |
| LMArena Text: mathematical work | Not measured | 1534 | Only Gemini 4 Hydrogen measured |
| MathArena | 82.8% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| AA-Omniscience | 66.8 | 46.3 | Claude Fable 5.2 |
| SimpleQA Verified | 94.0% | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text: science | Not measured | 1519 | Only Gemini 4 Hydrogen measured |
| LMArena Text: medicine and healthcare | Not measured | 1488 | Only Gemini 4 Hydrogen measured |
| LMArena Text: legal and government | Not measured | 1532 | Only Gemini 4 Hydrogen measured |
| LMArena Text: business and finance | Not measured | 1486 | Only Gemini 4 Hydrogen measured |
| PRBench Finance | 47.1% | Not measured | Only Claude Fable 5.2 measured |
| PRBench Legal | 49.0% | Not measured | Only Claude Fable 5.2 measured |
| Neither model has a result on the other 13 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| Design Arena: websites | 1351 | 1320 | Claude Fable 5.2 |
| Design Arena: UI components | 1371 | Not measured | Only Claude Fable 5.2 measured |
| Design Arena: game dev | 1396 | 1369 | Claude Fable 5.2 |
| Design Arena: 3D | 1517 | 1415 | Claude Fable 5.2 |
| Design Arena: all code categories | 1373 | 1333 | Claude Fable 5.2 |
| LiveBench design | 85.1% | 77.3% | Claude Fable 5.2 |
| Neither model has a result on the other 3 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index11
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| Vals Index | 71.3% | 68.5% | Claude Fable 5.2 |
| LiveBench data analysis | 81.5% | 83.2% | Gemini 4 Hydrogen |
| Long context reasoning (AA-LCR) | 83.3% | Not measured | Only Claude Fable 5.2 measured |
| GDPval-AA | 1831 | Not measured | Only Claude Fable 5.2 measured |
| DTBench | 99.2% | Not measured | Only Claude Fable 5.2 measured |
| LMCA | 70.6% | Not measured | Only Claude Fable 5.2 measured |
| Furniture assembly | 90.0% | Not measured | Only Claude Fable 5.2 measured |
| LMArena Text | Not measured | 1502 | Only Gemini 4 Hydrogen measured |
| LMArena Text: instruction following | Not measured | 1519 | Only Gemini 4 Hydrogen measured |
| LMArena Text: creative writing | Not measured | 1509 | Only Gemini 4 Hydrogen measured |
| LMArena Text: English | Not measured | 1499 | Only Gemini 4 Hydrogen measured |
| LMArena Text: non-English | Not measured | 1495 | Only Gemini 4 Hydrogen measured |
| LMArena Text: Chinese | Not measured | 1631 | Only Gemini 4 Hydrogen measured |
| LMArena Text: French | Not measured | 1512 | Only Gemini 4 Hydrogen measured |
| LMArena Text: Spanish | Not measured | 1494 | Only Gemini 4 Hydrogen measured |
| LMArena Text: Russian | Not measured | 1492 | Only Gemini 4 Hydrogen measured |
| LMArena Text: multi-turn | Not measured | 1485 | Only Gemini 4 Hydrogen measured |
| LMArena Text: longer queries | Not measured | 1524 | Only Gemini 4 Hydrogen measured |
| LMArena Text: writing and language | Not measured | 1500 | Only Gemini 4 Hydrogen measured |
| LMArena Text: entertainment and media | Not measured | 1503 | Only Gemini 4 Hydrogen measured |
| Neither model has a result on the other 29 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Fable 5.2 | Gemini 4 Hydrogen | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Gemini 4 Hydrogen costs less
Repository review
50K input + 3K output tokens
Gemini 4 Hydrogen costs less
Agent loop
200K input + 10K output tokens
Gemini 4 Hydrogen costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | Anthropic Claude Fable 5.2 | Google Gemini 4 Hydrogen |
|---|---|---|
| Maker | Anthropic | |
| Weights | No public weights listed | No public weights listed |
| Released | November 9, 2026 | November 12, 2026 |
| Context window | 1M | 1.05M |
| Input $/Mtok | $8.00 | $1.50 |
| Output $/Mtok | $40.00 | $7.50 |
| Coding index | 87.8 | 77.9 |
| Independent measurements behind it | 4 | 4 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Fable 5.2 better than Gemini 4 Hydrogen for coding?
Pick Claude Fable 5.2 for coding: it scores 87.8 on the Vibe Coding Index against 77.9 for Gemini 4 Hydrogen. Pick Gemini 4 Hydrogen for output tokens 5.3x cheaper ($7.50 vs $40.00 per million) and a larger context window (1.05M against 1M tokens).
Which is cheaper, Claude Fable 5.2 or Gemini 4 Hydrogen?
Claude Fable 5.2 costs $8.00 per million input tokens and $40.00 per million output tokens; Gemini 4 Hydrogen costs $1.50 and $7.50. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Fable 5.2 or Gemini 4 Hydrogen?
Gemini 4 Hydrogen, with 1.05M tokens against 1M.
How many benchmarks is the Claude Fable 5.2 vs Gemini 4 Hydrogen comparison based on?
26 benchmarks have a result for both models as of November 14, 2026. Claude Fable 5.2's coding index rests on 4 independent benchmarks and Gemini 4 Hydrogen's on 4. Where only one model has a result, the page says so instead of naming a winner.