Gemini 3.5 Flash Lite vs o3
Gemini 3.5 Flash Lite leads o3 on the Artificial Analysis Intelligence Index, 22.2 to 20.2, and Gemini 3.5 Flash Lite costs 3.2x less per output token ($2.50 vs $8.00 per million). Updated October 21, 2026; 65 benchmarks have a result for both.
Gemini 3.5 Flash Lite or o3: which to pick
Only Gemini 3.5 Flash Lite has a coding score, 49.0 on the Vibe Coding Index; o3 has none, so the two cannot be ranked on coding.
Pick o3 for work measured by LiveCodeBench (Vals AI) or WeirdML, where it leads.
- Shared results
- 65
- Gemini 3.5 Flash Lite only
- 20
- o3 only
- 37
- 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
No call
Only Gemini 3.5 Flash Lite has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite leads, 22.2 against 20.2.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Gemini 3.5 Flash Lite has a AA Agentic Index result, 14.3.
Directional only
Reasoning
GPQA Diamond
o3
o3 leads, 84.1% against 83.8%.
Same board, both measured
Math
AIME
No call
Only o3 has a AIME result, 85.3%.
Directional only
Knowledge
MMLU Pro
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite leads, 85.8% against 85.6%.
Same board, both measured
Web design
Design Arena: websites
No call
Only o3 has a Design Arena: websites result, 1036.
Directional only
Long documents
Listed context window
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite takes 1.05M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite $0.0015, o3 $0.0060 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite $0.41, o3 $0.571.
Published attempt cost and pass rate
At a glance
- Coding index
- Gemini 3.5 Flash Lite 49.0 from 3 benchmarks, o3 not benchmarked.
- Widest category
- Coding, 6.8 points apart on average over 6 shared benchmarks.
- Widest single gap
- Chess puzzles: Gemini 3.5 Flash Lite 21.0% against o3 37.0%, 16.0 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.5 Flash Lite $2.50 against o3 $8.00 per million output tokens, 3.2x apart.
- Context window
- Gemini 3.5 Flash Lite takes 1.05M tokens, o3 200K.
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 3.5 Flash Lite | Bars | o3 | Ties |
|---|---|---|---|---|
| Coding | 2 | 4 | ||
| Intelligence | 1 | 1 | ||
| Reasoning | 9 | 5 | ||
| Math | 2 | 2 | ||
| Knowledge | 8 | 3 | ||
| General | 24 | 4 | ||
| All shared boards | 46 | 19 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index24
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 81.3% | Only o3 measured |
| SWE-bench Verified | Not measured | 58.4% | Only o3 measured |
| SWE-bench Multimodal | Not measured | 36.0% | Only o3 measured |
| LMArena WebDev | 1435 | Not measured | Only Gemini 3.5 Flash Lite measured |
| AA Coding Index | 49.3 | Not measured | Only Gemini 3.5 Flash Lite measured |
| LiveCodeBench (Vals AI) | 79.0% | 83.9% | o3 |
| SWE-bench Verified (Vals AI) | 75.0% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Vibe Code Bench (Vals AI) | 37.2% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Code migration (Vals AI) | 6.2% | Not measured | Only Gemini 3.5 Flash Lite measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Terminal-Bench 2.1 (Vals AI) | 50.2% | Not measured | Only Gemini 3.5 Flash Lite measured |
| CyberBench (Vals AI) | 59.1% | Not measured | Only Gemini 3.5 Flash Lite measured |
| LiveCodeBench (Artificial Analysis run) | Not measured | 80.8% | Only o3 measured |
| SciCode | 41.3% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 37.1% | Only o3 measured |
| GSO-Bench | Not measured | 8.8% | Only o3 measured |
| WeirdML | 39.0% | 52.4% | o3 |
| ALE-Bench | 765.3 | 933.5 | o3 |
| LMArena Text: coding | 1453 | 1407 | Gemini 3.5 Flash Lite |
| LMArena Text: software and IT | 1451 | 1415 | Gemini 3.5 Flash Lite |
| LMArena WebDev: React | 1408 | Not measured | Only Gemini 3.5 Flash Lite measured |
| LMArena WebDev: from an image | 1448 | Not measured | Only Gemini 3.5 Flash Lite measured |
| SciCode | 6.2% | 9.2% | o3 |
| Neither model has a result on the other 16 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index11
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| AA Intelligence Index | 22.2 | 20.2 | Gemini 3.5 Flash Lite |
| Epoch Capabilities Index | 144.9 | 146.7 | o3 |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index13 boards, none shared
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| AA Agentic Index | 14.3 | Not measured | Only Gemini 3.5 Flash Lite measured |
| Finance Agent (Vals AI) | 47.4% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Tax Agent Bench (Vals AI) | 7.2% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Legal Research Bench (Vals AI) | 13.9% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Excel Modeling Benchmark (Vals AI) | 43.2% | Not measured | Only Gemini 3.5 Flash Lite measured |
| τ²-Bench Telecom | Not measured | 80.7% | Only o3 measured |
| APEX-Agents | 29.3% | Not measured | Only Gemini 3.5 Flash Lite measured |
| METR time horizons | Not measured | 65.4% | Only o3 measured |
| GDPval | Not measured | 30.8% | Only o3 measured |
| DeepResearch Bench | Not measured | 45.2% | Only o3 measured |
| OSWorld | Not measured | 23.0% | Only o3 measured |
| Berkeley Function Calling Leaderboard (BFCL) | Not measured | 63.0% | Only o3 measured |
| BrowseComp-Plus | Not measured | 65.9% | Only o3 measured |
| Neither model has a result on the other 28 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index95
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| GPQA Diamond | 83.8% | 84.1% | o3 |
| MMMU Pro (Vals AI) | 83.6% | 80.4% | Gemini 3.5 Flash Lite |
| GPQA Diamond (Artificial Analysis run) | 83.8% | 82.7% | Gemini 3.5 Flash Lite |
| Humanity's Last Exam (Artificial Analysis run) | 18.8% | 20.1% | o3 |
| GPQA Diamond (Epoch AI run) | 83.3% | 81.8% | Gemini 3.5 Flash Lite |
| ARC-AGI | 53.5% | 60.8% | o3 |
| ARC-AGI-2 | 10.3% | 6.5% | Gemini 3.5 Flash Lite |
| SimpleBench | Not measured | 53.1% | Only o3 measured |
| Chess puzzles | 21.0% | 37.0% | o3 |
| Mystery game puzzles | 19.0% | 29.0% | o3 |
| VPCT | Not measured | 52.0% | Only o3 measured |
| LMArena Text: hard prompts | 1441 | 1402 | Gemini 3.5 Flash Lite |
| LMArena Text: expert | 1434 | 1402 | Gemini 3.5 Flash Lite |
| LMArena Text: hard prompts in English | 1440 | 1411 | Gemini 3.5 Flash Lite |
| LMArena Vision: diagrams | 1284 | 1220 | Gemini 3.5 Flash Lite |
| LMArena Vision: homework | 1291 | 1234 | Gemini 3.5 Flash Lite |
| Kagi LLM Benchmark | Not measured | 67.6% | Only o3 measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index22
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| AIME | Not measured | 85.3% | Only o3 measured |
| MATH 500 (Vals AI) | Not measured | 94.6% | Only o3 measured |
| MGSM (Vals AI) | Not measured | 91.8% | Only o3 measured |
| AA Math Index | Not measured | 88.3 | Only o3 measured |
| AIME 2025 (Artificial Analysis run) | Not measured | 88.3% | Only o3 measured |
| OTIS Mock AIME | 71.1% | 84.4% | o3 |
| FrontierMath, tiers 1 to 3 | 26.0% | 33.3% | o3 |
| FrontierMath, tier 4 | 0.0% | Not measured | Only Gemini 3.5 Flash Lite measured |
| ProofBench | 13.0% | Not measured | Only Gemini 3.5 Flash Lite measured |
| MATH level 5 | Not measured | 97.8% | Only o3 measured |
| LMArena Text: math | 1434 | 1426 | Gemini 3.5 Flash Lite |
| LMArena Text: mathematical work | 1433 | 1423 | Gemini 3.5 Flash Lite |
| Neither model has a result on the other 1 board here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index83
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| MMLU Pro | 85.8% | 85.6% | Gemini 3.5 Flash Lite |
| LegalBench (Vals AI) | 84.1% | 83.8% | Gemini 3.5 Flash Lite |
| CorpFin (Vals AI) | 60.7% | 59.7% | Gemini 3.5 Flash Lite |
| TaxEval (Vals AI) | 72.6% | 74.6% | o3 |
| MortgageTax (Vals AI) | 68.7% | 65.7% | Gemini 3.5 Flash Lite |
| MedQA (Vals AI) | Not measured | 96.1% | Only o3 measured |
| MedCode (Vals AI) | 43.5% | 47.3% | o3 |
| MMLU Pro (Artificial Analysis run) | Not measured | 85.3% | Only o3 measured |
| SimpleQA Verified | Not measured | 49.4% | Only o3 measured |
| GeoBench | Not measured | 74.0% | Only o3 measured |
| LMArena Text: science | 1451 | 1429 | Gemini 3.5 Flash Lite |
| LMArena Text: medicine and healthcare | 1438 | 1448 | o3 |
| LMArena Text: legal and government | 1431 | 1428 | Gemini 3.5 Flash Lite |
| LMArena Text: business and finance | 1423 | 1393 | Gemini 3.5 Flash Lite |
| FACTS Benchmark Suite | 53.5% | 44.4% | Gemini 3.5 Flash Lite |
| Neither model has a result on the other 3 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index5 boards, none shared
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| Design Arena: websites | Not measured | 1036 | Only o3 measured |
| Design Arena: UI components | Not measured | 1017 | Only o3 measured |
| Design Arena: game dev | Not measured | 1034 | Only o3 measured |
| Design Arena: data viz | Not measured | 1200 | Only o3 measured |
| Design Arena: all code categories | Not measured | 1020 | Only o3 measured |
| Neither model has a result on the other 4 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index244
| Benchmark | Gemini 3.5 Flash Lite | o3 | Leader |
|---|---|---|---|
| Public Benefits Bench (Vals AI) | 51.8% | Not measured | Only Gemini 3.5 Flash Lite measured |
| SAGE (Vals AI) | 47.3% | 41.8% | Gemini 3.5 Flash Lite |
| MedScribe (Vals AI) | 70.9% | 76.7% | o3 |
| IFBench | Not measured | 71.4% | Only o3 measured |
| Long context reasoning (AA-LCR) | 76.0% | 74.7% | Gemini 3.5 Flash Lite |
| DTBench | 83.5% | 84.8% | o3 |
| LMCA | 37.6% | 39.7% | o3 |
| Fiction.LiveBench | Not measured | 88.9% | Only o3 measured |
| Creative writing (Lech Mazur) | Not measured | 83.9% | Only o3 measured |
| CL-bench | Not measured | 17.8% | Only o3 measured |
| LMArena Text | 1435 | 1410 | Gemini 3.5 Flash Lite |
| LMArena Text: instruction following | 1419 | 1368 | Gemini 3.5 Flash Lite |
| LMArena Text: creative writing | 1421 | 1359 | Gemini 3.5 Flash Lite |
| LMArena Vision | 1269 | 1214 | Gemini 3.5 Flash Lite |
| LMArena Text: English | 1438 | 1417 | Gemini 3.5 Flash Lite |
| LMArena Text: non-English | 1427 | 1401 | Gemini 3.5 Flash Lite |
| LMArena Text: Chinese | 1468 | 1437 | Gemini 3.5 Flash Lite |
| LMArena Text: German | 1454 | 1420 | Gemini 3.5 Flash Lite |
| LMArena Text: Japanese | 1426 | 1403 | Gemini 3.5 Flash Lite |
| LMArena Text: Korean | 1407 | 1370 | Gemini 3.5 Flash Lite |
| LMArena Text: French | 1451 | 1430 | Gemini 3.5 Flash Lite |
| LMArena Text: Spanish | 1441 | 1395 | Gemini 3.5 Flash Lite |
| LMArena Text: Russian | 1443 | 1406 | Gemini 3.5 Flash Lite |
| LMArena Text: Polish | 1437 | 1438 | o3 |
| LMArena Text: multi-turn | 1445 | 1405 | Gemini 3.5 Flash Lite |
| LMArena Text: longer queries | 1435 | 1372 | Gemini 3.5 Flash Lite |
| LMArena Text: writing and language | 1428 | 1372 | Gemini 3.5 Flash Lite |
| LMArena Text: entertainment and media | 1414 | 1373 | Gemini 3.5 Flash Lite |
| LMArena Vision: English | 1269 | 1221 | Gemini 3.5 Flash Lite |
| LMArena Vision: Chinese | 1311 | 1237 | Gemini 3.5 Flash Lite |
| LMArena Vision: reading text | 1280 | 1218 | Gemini 3.5 Flash Lite |
| LMArena Vision: humor | 1287 | 1222 | Gemini 3.5 Flash Lite |
| LMArena Vision: captioning | Not measured | 1210 | Only o3 measured |
| LMArena Vision: recognizing things | Not measured | 1234 | Only o3 measured |
| LMArena Vision: creative writing | 1260 | 1201 | Gemini 3.5 Flash Lite |
| Neither model has a result on the other 11 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.5 Flash Lite | o3 | 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 3.5 Flash Lite costs less
Repository review
50K input + 3K output tokens
Gemini 3.5 Flash Lite costs less
Agent loop
200K input + 10K output tokens
Gemini 3.5 Flash Lite 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 3.5 Flash Lite | OpenAI o3 |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | No public weights listed |
| Released | July 21, 2026 | April 16, 2025 |
| Context window | 1.05M | 200K |
| Input $/Mtok | $0.30 | $2.00 |
| Output $/Mtok | $2.50 | $8.00 |
| Coding index | 49.0 | Not benchmarked |
| Independent measurements behind it | 3 | 0 |
| Cost per solved task | $0.41 | $0.571 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.5 Flash Lite better than o3 for coding?
Only Gemini 3.5 Flash Lite has a coding score, 49.0 on the Vibe Coding Index; o3 has none, so the two cannot be ranked on coding. Pick o3 for work measured by LiveCodeBench (Vals AI) or WeirdML, where it leads.
Which is cheaper, Gemini 3.5 Flash Lite or o3?
Gemini 3.5 Flash Lite costs $0.30 per million input tokens and $2.50 per million output tokens; o3 costs $2.00 and $8.00. Per solved SWE-bench Verified task, Gemini 3.5 Flash Lite costs $0.41 and o3 $0.571.
Which has the bigger context window, Gemini 3.5 Flash Lite or o3?
Gemini 3.5 Flash Lite, with 1.05M tokens against 200K.
How many benchmarks is the Gemini 3.5 Flash Lite vs o3 comparison based on?
65 benchmarks have a result for both models as of October 21, 2026. Gemini 3.5 Flash Lite's coding index rests on 3 independent benchmarks and o3's on 0. Where only one model has a result, the page says so instead of naming a winner.