Gemini 3.1 Flash Lite Preview vs Mercury 2
Gemini 3.1 Flash Lite Preview leads Mercury 2 on the Artificial Analysis Intelligence Index, 15.6 to 10.8, and Mercury 2 costs 2.0x less per output token ($0.75 vs $1.50 per million). Updated October 22, 2026; 34 benchmarks have a result for both.
Gemini 3.1 Flash Lite Preview or Mercury 2: which to pick
Only Gemini 3.1 Flash Lite Preview has a coding score, 22.7 on the Vibe Coding Index; Mercury 2 has none, so the two cannot be ranked on coding.
Pick Mercury 2 for output tokens 2.0x cheaper ($0.75 vs $1.50 per million).
- Shared results
- 34
- Gemini 3.1 Flash Lite Preview only
- 45
- Mercury 2 only
- 8
- Like-for-like categories
- 7 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
No call
Only Gemini 3.1 Flash Lite Preview has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Gemini 3.1 Flash Lite Preview
Gemini 3.1 Flash Lite Preview leads, 15.6 against 10.8.
Same board, both measured
Agentic work
AA Agentic Index
No call
Tied at 1.6.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Gemini 3.1 Flash Lite Preview has a GPQA Diamond result, 81.1%.
Directional only
Math
AIME
No call
Only Gemini 3.1 Flash Lite Preview has a AIME result, 83.3%.
Directional only
Knowledge
MMLU Pro
No call
Only Gemini 3.1 Flash Lite Preview has a MMLU Pro result, 86.2%.
Directional only
Web design
Design Arena: websites
Gemini 3.1 Flash Lite Preview
Gemini 3.1 Flash Lite Preview leads, 1082 against 1036.
Same board, both measured
Long documents
Listed context window
Gemini 3.1 Flash Lite Preview
Gemini 3.1 Flash Lite Preview takes 1.05M tokens against 128K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Mercury 2
Gemini 3.1 Flash Lite Preview $0.0010, Mercury 2 $0.0006 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3.1 Flash Lite Preview has the number, $0.18.
Directional only
At a glance
- Coding index
- Gemini 3.1 Flash Lite Preview 22.7 from 3 benchmarks, Mercury 2 not benchmarked.
- Widest category
- General, 12.2 points apart on average over 11 shared benchmarks.
- Widest single gap
- Design Arena: ASCII art: Gemini 3.1 Flash Lite Preview 1167 against Mercury 2 988, 22.4 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.1 Flash Lite Preview $1.50 against Mercury 2 $0.75 per million output tokens, 2.0x apart.
- Context window
- Gemini 3.1 Flash Lite Preview takes 1.05M tokens, Mercury 2 128K.
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 | Gemini 3.1 Flash Lite Preview | Bars | Mercury 2 | Ties |
|---|---|---|---|---|
| Coding | 7 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 0 | 0 | 1 tie | |
| Reasoning | 3 | 0 | ||
| Knowledge | 3 | 0 | ||
| Web design | 8 | 0 | ||
| General | 11 | 0 | ||
| All shared boards | 33 | 0 | 1 tie |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index70
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| LMArena WebDev | 1257 | 1171 | Gemini 3.1 Flash Lite Preview |
| AA Coding Index | 34.7 | 31.1 | Gemini 3.1 Flash Lite Preview |
| LiveCodeBench (Vals AI) | 80.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| SWE-bench Verified (Vals AI) | 62.8% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Vibe Code Bench (Vals AI) | 0.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Code migration (Vals AI) | 4.6% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Terminal-Bench 2.1 (Vals AI) | 34.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| SciCode | Not measured | 37.7% | Only Mercury 2 measured |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 26.5% | Only Mercury 2 measured |
| WeirdML | Not measured | 43.2% | Only Mercury 2 measured |
| ALE-Bench | 797.7 | 785.6 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: coding | 1400 | 1390 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: software and IT | 1413 | 1385 | Gemini 3.1 Flash Lite Preview |
| LMArena WebDev: React | 1245 | 1160 | Gemini 3.1 Flash Lite Preview |
| LMArena WebDev: HTML | 1276 | 1199 | Gemini 3.1 Flash Lite Preview |
| LMArena WebDev: from an image | 1336 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| SciCode | 4.6% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 21 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| AA Intelligence Index | 15.6 | 10.8 | Gemini 3.1 Flash Lite Preview |
| Neither model has a result on the other 1 board here | |||
Agentic workLike-for-likePublic boards, shown as published, kept out of the index00
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| AA Agentic Index | 1.6 | 1.6 | Tie |
| Finance Agent (Vals AI) | 30.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Tax Agent Bench (Vals AI) | 3.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Legal Research Bench (Vals AI) | 3.4% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Excel Modeling Benchmark (Vals AI) | 8.6% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| τ²-Bench Telecom | Not measured | 70.8% | Only Mercury 2 measured |
| Neither model has a result on the other 35 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| GPQA Diamond | 81.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MMMU Pro (Vals AI) | 82.5% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 77.0% | Only Mercury 2 measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 17.1% | Only Mercury 2 measured |
| LMArena Text: hard prompts | 1407 | 1362 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: expert | 1398 | 1358 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: hard prompts in English | 1403 | 1374 | Gemini 3.1 Flash Lite Preview |
| LMArena Vision: diagrams | 1242 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: homework | 1271 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 13 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index3 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| AIME | 83.3% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: math | 1428 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: mathematical work | 1417 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 10 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| MMLU Pro | 86.2% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LegalBench (Vals AI) | 83.8% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| CaseLaw (Vals AI) | 55.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| CorpFin (Vals AI) | 59.4% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| TaxEval (Vals AI) | 71.8% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MortgageTax (Vals AI) | 68.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MedCode (Vals AI) | 47.6% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: science | 1425 | 1343 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: medicine and healthcare | 1428 | 1363 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: legal and government | 1418 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: business and finance | 1389 | 1349 | Gemini 3.1 Flash Lite Preview |
| FACTS Benchmark Suite | 51.4% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| Design Arena: websites | 1082 | 1036 | Gemini 3.1 Flash Lite Preview |
| Design Arena: UI components | 1069 | 996 | Gemini 3.1 Flash Lite Preview |
| Design Arena: game dev | 1029 | 984 | Gemini 3.1 Flash Lite Preview |
| Design Arena: data viz | 1045 | 1009 | Gemini 3.1 Flash Lite Preview |
| Design Arena: 3D | 1047 | 982 | Gemini 3.1 Flash Lite Preview |
| Design Arena: all code categories | 1072 | 1021 | Gemini 3.1 Flash Lite Preview |
| Design Arena: SVG | 1052 | 998 | Gemini 3.1 Flash Lite Preview |
| Design Arena: ASCII art | 1167 | 988 | Gemini 3.1 Flash Lite Preview |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index110
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 49.5% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MedScribe (Vals AI) | 63.9% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Vals Multimodal Index | 41.4% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| IFBench | Not measured | 69.8% | Only Mercury 2 measured |
| Long context reasoning (AA-LCR) | Not measured | 43.7% | Only Mercury 2 measured |
| LMArena Text | 1416 | 1354 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: instruction following | 1377 | 1328 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: creative writing | 1401 | 1286 | Gemini 3.1 Flash Lite Preview |
| LMArena Vision | 1240 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: English | 1414 | 1378 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: non-English | 1410 | 1330 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: Chinese | 1460 | 1414 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: German | 1430 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Japanese | 1413 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Korean | 1392 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: French | 1424 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Spanish | 1421 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Russian | 1420 | 1304 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: Polish | 1443 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: multi-turn | 1417 | 1357 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: longer queries | 1394 | 1329 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: writing and language | 1408 | 1300 | Gemini 3.1 Flash Lite Preview |
| LMArena Text: entertainment and media | 1386 | 1314 | Gemini 3.1 Flash Lite Preview |
| LMArena Vision: English | 1232 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: Chinese | 1278 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: reading text | 1246 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: humor | 1266 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: captioning | 1259 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: recognizing things | 1308 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: creative writing | 1248 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 16 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | Mercury 2 | 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
Mercury 2 costs less
Repository review
50K input + 3K output tokens
Mercury 2 costs less
Agent loop
200K input + 10K output tokens
Mercury 2 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 | Google Gemini 3.1 Flash Lite Preview | Inception Mercury 2 |
|---|---|---|
| Maker | Inception | |
| Weights | No public weights listed | No public weights listed |
| Released | March 3, 2026 | March 4, 2026 |
| Context window | 1.05M | 128K |
| Input $/Mtok | $0.25 | $0.25 |
| Output $/Mtok | $1.50 | $0.75 |
| Coding index | 22.7 | Not benchmarked |
| Independent measurements behind it | 3 | 1 |
| Cost per solved task | $0.18 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.1 Flash Lite Preview better than Mercury 2 for coding?
Only Gemini 3.1 Flash Lite Preview has a coding score, 22.7 on the Vibe Coding Index; Mercury 2 has none, so the two cannot be ranked on coding. Pick Mercury 2 for output tokens 2.0x cheaper ($0.75 vs $1.50 per million).
Which is cheaper, Gemini 3.1 Flash Lite Preview or Mercury 2?
Gemini 3.1 Flash Lite Preview costs $0.25 per million input tokens and $1.50 per million output tokens; Mercury 2 costs $0.25 and $0.75. Cost per solved task is known for Gemini 3.1 Flash Lite Preview only.
Which has the bigger context window, Gemini 3.1 Flash Lite Preview or Mercury 2?
Gemini 3.1 Flash Lite Preview, with 1.05M tokens against 128K.
How many benchmarks is the Gemini 3.1 Flash Lite Preview vs Mercury 2 comparison based on?
34 benchmarks have a result for both models as of October 22, 2026. Gemini 3.1 Flash Lite Preview's coding index rests on 3 independent benchmarks and Mercury 2's on 1. Where only one model has a result, the page says so instead of naming a winner.