Gemini 2.5 Flash Lite vs Gemini 3.1 Flash Lite
Gemini 2.5 Flash Lite costs 3.8x less per output token than Gemini 3.1 Flash Lite ($0.40 vs $1.50 per million). Updated October 21, 2026; 9 benchmarks have a result for both.
Gemini 2.5 Flash Lite or Gemini 3.1 Flash Lite: which to pick
Neither model has a coding score yet, so the two cannot be ranked on coding.
Pick Gemini 2.5 Flash Lite for output tokens 3.8x cheaper ($0.40 vs $1.50 per million) and work measured by Terminal-Bench Hard (Artificial Analysis run) or Epoch Capabilities Index, where it leads.
- Shared results
- 9
- Gemini 2.5 Flash Lite only
- 19
- Gemini 3.1 Flash Lite only
- 6
- Like-for-like categories
- 5 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
Neither has a coding score yet.
One side not measured
Intelligence
AA Intelligence Index
No call
Only Gemini 2.5 Flash Lite has a AA Intelligence Index result, 10.4.
Directional only
Reasoning
GPQA Diamond
No call
Only Gemini 2.5 Flash Lite has a GPQA Diamond result, 70.2%.
Directional only
Math
AIME
No call
Only Gemini 2.5 Flash Lite has a AIME result, 42.1%.
Directional only
Knowledge
MMLU Pro
No call
Only Gemini 2.5 Flash Lite has a MMLU Pro result, 79.1%.
Directional only
Long documents
Listed context window
No call
Both take 1.05M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 2.5 Flash Lite
Gemini 2.5 Flash Lite $0.0003, Gemini 3.1 Flash Lite $0.0010 per turn.
List prices
At a glance
- Coding index
- Gemini 2.5 Flash Lite not benchmarked, Gemini 3.1 Flash Lite not benchmarked.
- Widest category
- Coding, 19.7 points apart on average over 1 shared benchmark.
- Widest single gap
- IFBench: Gemini 2.5 Flash Lite 49.9% against Gemini 3.1 Flash Lite 77.2%, 27.3 points apart on a 0 to 100 scale.
- Output price
- Gemini 2.5 Flash Lite $0.40 against Gemini 3.1 Flash Lite $1.50 per million output tokens, 3.8x apart.
- Context window
- Both take 1.05M tokens.
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 2.5 Flash Lite | Bars | Gemini 3.1 Flash Lite | Ties |
|---|---|---|---|---|
| Coding | 0 | 1 | ||
| Intelligence | 0 | 1 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 0 | 2 | ||
| General | 0 | 4 | ||
| All shared boards | 0 | 9 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index01
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| LiveCodeBench (Vals AI) | 71.4% | Not measured | Only Gemini 2.5 Flash Lite measured |
| LiveCodeBench (Artificial Analysis run) | 59.3% | Not measured | Only Gemini 2.5 Flash Lite measured |
| SciCode | Not measured | 43.4% | Only Gemini 3.1 Flash Lite measured |
| Terminal-Bench Hard (Artificial Analysis run) | 4.5% | 24.2% | Gemini 3.1 Flash Lite |
| WeirdML | Not measured | 52.2% | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 33 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| AA Intelligence Index | 10.4 | Not measured | Only Gemini 2.5 Flash Lite measured |
| Epoch Capabilities Index | 133.8 | 144.3 | Gemini 3.1 Flash Lite |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| τ²-Bench Telecom | 19.0% | 31.3% | Gemini 3.1 Flash Lite |
| DeepResearch Bench | Not measured | 37.3% | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 37 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| GPQA Diamond | 70.2% | Not measured | Only Gemini 2.5 Flash Lite measured |
| MMMU Pro (Vals AI) | 75.4% | Not measured | Only Gemini 2.5 Flash Lite measured |
| GPQA Diamond (Artificial Analysis run) | 62.5% | 82.2% | Gemini 3.1 Flash Lite |
| Humanity's Last Exam (Artificial Analysis run) | 6.8% | 17.2% | Gemini 3.1 Flash Lite |
| GPQA Diamond (Epoch AI run) | Not measured | 81.8% | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 16 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| AIME | 42.1% | Not measured | Only Gemini 2.5 Flash Lite measured |
| MGSM (Vals AI) | 89.5% | Not measured | Only Gemini 2.5 Flash Lite measured |
| AA Math Index | 53.3 | Not measured | Only Gemini 2.5 Flash Lite measured |
| AIME 2025 (Artificial Analysis run) | 53.3% | Not measured | Only Gemini 2.5 Flash Lite measured |
| OTIS Mock AIME | Not measured | 80.0% | Only Gemini 3.1 Flash Lite measured |
| FrontierMath, tiers 1 to 3 | Not measured | 27.7% | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| MMLU Pro | 79.1% | Not measured | Only Gemini 2.5 Flash Lite measured |
| LegalBench (Vals AI) | 82.0% | Not measured | Only Gemini 2.5 Flash Lite measured |
| CorpFin (Vals AI) | 57.6% | Not measured | Only Gemini 2.5 Flash Lite measured |
| TaxEval (Vals AI) | 66.2% | Not measured | Only Gemini 2.5 Flash Lite measured |
| MortgageTax (Vals AI) | 57.6% | Not measured | Only Gemini 2.5 Flash Lite measured |
| MedQA (Vals AI) | 88.9% | Not measured | Only Gemini 2.5 Flash Lite measured |
| MedCode (Vals AI) | 34.2% | Not measured | Only Gemini 2.5 Flash Lite measured |
| MMLU Pro (Artificial Analysis run) | 75.9% | Not measured | Only Gemini 2.5 Flash Lite measured |
| Neither model has a result on the other 9 boards here | |||
Web designNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| Neither model has a result on 9 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 30.8% | Not measured | Only Gemini 2.5 Flash Lite measured |
| MedScribe (Vals AI) | 75.8% | Not measured | Only Gemini 2.5 Flash Lite measured |
| IFBench | 49.9% | 77.2% | Gemini 3.1 Flash Lite |
| Long context reasoning (AA-LCR) | 55.7% | 74.3% | Gemini 3.1 Flash Lite |
| DTBench | 62.8% | 76.8% | Gemini 3.1 Flash Lite |
| LMCA | 18.1% | 35.0% | Gemini 3.1 Flash Lite |
| Neither model has a result on the other 40 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 2.5 Flash Lite | Gemini 3.1 Flash Lite | 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 2.5 Flash Lite costs less
Repository review
50K input + 3K output tokens
Gemini 2.5 Flash Lite costs less
Agent loop
200K input + 10K output tokens
Gemini 2.5 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 2.5 Flash Lite | Google Gemini 3.1 Flash Lite |
|---|---|---|
| Maker | ||
| Weights | No public weights listed | No public weights listed |
| Released | July 22, 2025 | May 7, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $0.10 | $0.25 |
| Output $/Mtok | $0.40 | $1.50 |
| Coding index | Not benchmarked | Not benchmarked |
| Independent measurements behind it | 0 | 0 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 2.5 Flash Lite better than Gemini 3.1 Flash Lite for coding?
Neither model has a coding score yet, so the two cannot be ranked on coding. Pick Gemini 2.5 Flash Lite for output tokens 3.8x cheaper ($0.40 vs $1.50 per million) and work measured by Terminal-Bench Hard (Artificial Analysis run) or Epoch Capabilities Index, where it leads.
Which is cheaper, Gemini 2.5 Flash Lite or Gemini 3.1 Flash Lite?
Gemini 2.5 Flash Lite costs $0.10 per million input tokens and $0.40 per million output tokens; Gemini 3.1 Flash Lite costs $0.25 and $1.50. Cost per solved task is known for neither of them.
Which has the bigger context window, Gemini 2.5 Flash Lite or Gemini 3.1 Flash Lite?
Neither: both take 1.05M tokens.
How many benchmarks is the Gemini 2.5 Flash Lite vs Gemini 3.1 Flash Lite comparison based on?
9 benchmarks have a result for both models as of October 21, 2026. Gemini 2.5 Flash Lite's coding index rests on 0 independent benchmarks and Gemini 3.1 Flash Lite's on 0. Where only one model has a result, the page says so instead of naming a winner.