Gemini 3.1 Flash Lite vs Step 3.5 Flash
Step 3.5 Flash costs 5.0x less per output token than Gemini 3.1 Flash Lite ($0.30 vs $1.50 per million). Updated October 21, 2026; 6 benchmarks have a result for both.
Gemini 3.1 Flash Lite or Step 3.5 Flash: which to pick
Neither model has a coding score yet, so the two cannot be ranked on coding.
Pick Gemini 3.1 Flash Lite for a larger context window (1.05M against 262K tokens) and work measured by Terminal-Bench Hard (Artificial Analysis run) or τ²-Bench Telecom, where it leads.
- Shared results
- 6
- Gemini 3.1 Flash Lite only
- 10
- Step 3.5 Flash only
- 29
- Like-for-like categories
- 4 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 Step 3.5 Flash has a AA Intelligence Index result, 17.0.
Directional only
Long documents
Listed context window
Gemini 3.1 Flash Lite
Gemini 3.1 Flash Lite takes 1.05M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Step 3.5 Flash
Gemini 3.1 Flash Lite $0.0010, Step 3.5 Flash $0.0003 per turn.
List prices
At a glance
- Coding index
- Gemini 3.1 Flash Lite not benchmarked, Step 3.5 Flash not benchmarked.
- Widest category
- Agentic work, 63.2 points apart on average over 1 shared benchmark.
- Widest single gap
- τ²-Bench Telecom: Gemini 3.1 Flash Lite 31.3% against Step 3.5 Flash 94.4%, 63.2 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.1 Flash Lite $1.50 against Step 3.5 Flash $0.30 per million output tokens, 5.0x apart.
- Context window
- Gemini 3.1 Flash Lite takes 1.05M tokens, Step 3.5 Flash 262K.
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 | Bars | Step 3.5 Flash | Ties |
|---|---|---|---|---|
| Coding | 0 | 1 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 0 | 2 | ||
| General | 2 | 0 | ||
| All shared boards | 2 | 4 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index01
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| SciCode | 43.4% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Terminal-Bench Hard (Artificial Analysis run) | 24.2% | 32.6% | Step 3.5 Flash |
| WeirdML | 52.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| LMArena Text: coding | Not measured | 1436 | Only Step 3.5 Flash measured |
| LMArena Text: software and IT | Not measured | 1434 | Only Step 3.5 Flash measured |
| Neither model has a result on the other 34 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | Not measured | 17.0 | Only Step 3.5 Flash measured |
| Epoch Capabilities Index | 144.3 | Not measured | Only Gemini 3.1 Flash Lite measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| τ²-Bench Telecom | 31.3% | 94.4% | Step 3.5 Flash |
| DeepResearch Bench | 37.3% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 39 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| GPQA Diamond (Artificial Analysis run) | 82.2% | 83.1% | Step 3.5 Flash |
| Humanity's Last Exam (Artificial Analysis run) | 17.2% | 24.5% | Step 3.5 Flash |
| GPQA Diamond (Epoch AI run) | 81.8% | Not measured | Only Gemini 3.1 Flash Lite measured |
| LMArena Text: hard prompts | Not measured | 1411 | Only Step 3.5 Flash measured |
| LMArena Text: expert | Not measured | 1421 | Only Step 3.5 Flash measured |
| LMArena Text: hard prompts in English | Not measured | 1421 | Only Step 3.5 Flash measured |
| Kagi LLM Benchmark | 67.2% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Neither model has a result on the other 15 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index4 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| OTIS Mock AIME | 80.0% | Not measured | Only Gemini 3.1 Flash Lite measured |
| FrontierMath, tiers 1 to 3 | 27.7% | Not measured | Only Gemini 3.1 Flash Lite measured |
| LMArena Text: math | Not measured | 1408 | Only Step 3.5 Flash measured |
| LMArena Text: mathematical work | Not measured | 1421 | Only Step 3.5 Flash measured |
| Neither model has a result on the other 9 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index4 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| LMArena Text: science | Not measured | 1415 | Only Step 3.5 Flash measured |
| LMArena Text: medicine and healthcare | Not measured | 1408 | Only Step 3.5 Flash measured |
| LMArena Text: legal and government | Not measured | 1408 | Only Step 3.5 Flash measured |
| LMArena Text: business and finance | Not measured | 1394 | Only Step 3.5 Flash measured |
| Neither model has a result on the other 14 boards here | |||
Web designNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| Neither model has a result on 9 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | Leader |
|---|---|---|---|
| IFBench | 77.2% | 66.5% | Gemini 3.1 Flash Lite |
| Long context reasoning (AA-LCR) | 74.3% | 63.0% | Gemini 3.1 Flash Lite |
| DTBench | 76.8% | Not measured | Only Gemini 3.1 Flash Lite measured |
| LMCA | 35.0% | Not measured | Only Gemini 3.1 Flash Lite measured |
| LMArena Text | Not measured | 1403 | Only Step 3.5 Flash measured |
| LMArena Text: instruction following | Not measured | 1385 | Only Step 3.5 Flash measured |
| LMArena Text: creative writing | Not measured | 1357 | Only Step 3.5 Flash measured |
| LMArena Text: English | Not measured | 1417 | Only Step 3.5 Flash measured |
| LMArena Text: non-English | Not measured | 1385 | Only Step 3.5 Flash measured |
| LMArena Text: Chinese | Not measured | 1446 | Only Step 3.5 Flash measured |
| LMArena Text: German | Not measured | 1405 | Only Step 3.5 Flash measured |
| LMArena Text: Japanese | Not measured | 1353 | Only Step 3.5 Flash measured |
| LMArena Text: Korean | Not measured | 1351 | Only Step 3.5 Flash measured |
| LMArena Text: French | Not measured | 1421 | Only Step 3.5 Flash measured |
| LMArena Text: Spanish | Not measured | 1419 | Only Step 3.5 Flash measured |
| LMArena Text: Russian | Not measured | 1385 | Only Step 3.5 Flash measured |
| LMArena Text: Polish | Not measured | 1389 | Only Step 3.5 Flash measured |
| LMArena Text: multi-turn | Not measured | 1404 | Only Step 3.5 Flash measured |
| LMArena Text: longer queries | Not measured | 1402 | Only Step 3.5 Flash measured |
| LMArena Text: writing and language | Not measured | 1372 | Only Step 3.5 Flash measured |
| LMArena Text: entertainment and media | Not measured | 1360 | Only Step 3.5 Flash measured |
| Neither model has a result on the other 25 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Step 3.5 Flash | 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
Step 3.5 Flash costs less
Repository review
50K input + 3K output tokens
Step 3.5 Flash costs less
Agent loop
200K input + 10K output tokens
Step 3.5 Flash 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 | StepFun Step 3.5 Flash |
|---|---|---|
| Maker | StepFun | |
| Weights | No public weights listed | Open weights |
| Released | May 7, 2026 | January 29, 2026 |
| Context window | 1.05M | 262K |
| Input $/Mtok | $0.25 | $0.10 |
| Output $/Mtok | $1.50 | $0.30 |
| 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 3.1 Flash Lite better than Step 3.5 Flash for coding?
Neither model has a coding score yet, so the two cannot be ranked on coding. Pick Gemini 3.1 Flash Lite for a larger context window (1.05M against 262K tokens) and work measured by Terminal-Bench Hard (Artificial Analysis run) or τ²-Bench Telecom, where it leads.
Which is cheaper, Gemini 3.1 Flash Lite or Step 3.5 Flash?
Gemini 3.1 Flash Lite costs $0.25 per million input tokens and $1.50 per million output tokens; Step 3.5 Flash costs $0.10 and $0.30. Cost per solved task is known for neither of them.
Which has the bigger context window, Gemini 3.1 Flash Lite or Step 3.5 Flash?
Gemini 3.1 Flash Lite, with 1.05M tokens against 262K.
How many benchmarks is the Gemini 3.1 Flash Lite vs Step 3.5 Flash comparison based on?
6 benchmarks have a result for both models as of October 21, 2026. Gemini 3.1 Flash Lite's coding index rests on 0 independent benchmarks and Step 3.5 Flash's on 0. Where only one model has a result, the page says so instead of naming a winner.