Reka Flash 3 vs Step 3.5 Flash
Step 3.5 Flash leads Reka Flash 3 on the Artificial Analysis Intelligence Index, 17.0 to 6.4, and Reka Flash 3 costs 1.5x less per output token ($0.20 vs $0.30 per million). Updated October 22, 2026; 7 benchmarks have a result for both.
Reka Flash 3 or Step 3.5 Flash: which to pick
Neither model has a coding score yet, so the two cannot be ranked on coding.
Pick Reka Flash 3 for output tokens 1.5x cheaper ($0.20 vs $0.30 per million) and work measured by Terminal-Bench Hard (Artificial Analysis run) or AA Intelligence Index, where it leads.
- Shared results
- 7
- Reka Flash 3 only
- 5
- Step 3.5 Flash only
- 28
- 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
Step 3.5 Flash
Step 3.5 Flash leads, 17.0 against 6.4.
Same board, both measured
Long documents
Listed context window
Step 3.5 Flash
Step 3.5 Flash takes 262K tokens against 66K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Reka Flash 3
Reka Flash 3 $0.0002, Step 3.5 Flash $0.0003 per turn.
List prices
At a glance
- Coding index
- Reka Flash 3 not benchmarked, Step 3.5 Flash not benchmarked.
- Widest category
- Agentic work, 94.4 points apart on average over 1 shared benchmark.
- Widest single gap
- τ²-Bench Telecom: Reka Flash 3 0.0% against Step 3.5 Flash 94.4%, 94.4 points apart on a 0 to 100 scale.
- Output price
- Reka Flash 3 $0.20 against Step 3.5 Flash $0.30 per million output tokens, 1.5x apart.
- Context window
- Reka Flash 3 takes 66K 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 | Reka Flash 3 | Bars | Step 3.5 Flash | Ties |
|---|---|---|---|---|
| Coding | 0 | 1 | ||
| Intelligence | 0 | 1 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 0 | 2 | ||
| General | 0 | 2 | ||
| All shared boards | 0 | 7 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index01
| Benchmark | Reka Flash 3 | Step 3.5 Flash | Leader |
|---|---|---|---|
| LiveCodeBench (Artificial Analysis run) | 43.5% | Not measured | Only Reka Flash 3 measured |
| Terminal-Bench Hard (Artificial Analysis run) | 0.0% | 32.6% | Step 3.5 Flash |
| 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 35 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Reka Flash 3 | Step 3.5 Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | 6.4 | 17.0 | Step 3.5 Flash |
| Neither model has a result on the other 1 board here | |||
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Reka Flash 3 | Step 3.5 Flash | Leader |
|---|---|---|---|
| τ²-Bench Telecom | 0.0% | 94.4% | Step 3.5 Flash |
| BALROG | 29.2% | Not measured | Only Reka Flash 3 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 | Reka Flash 3 | Step 3.5 Flash | Leader |
|---|---|---|---|
| GPQA Diamond (Artificial Analysis run) | 52.9% | 83.1% | Step 3.5 Flash |
| Humanity's Last Exam (Artificial Analysis run) | 4.4% | 24.5% | Step 3.5 Flash |
| 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 |
| Neither model has a result on the other 17 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index4 boards, none shared
| Benchmark | Reka Flash 3 | Step 3.5 Flash | Leader |
|---|---|---|---|
| AA Math Index | 33.7 | Not measured | Only Reka Flash 3 measured |
| AIME 2025 (Artificial Analysis run) | 33.7% | Not measured | Only Reka Flash 3 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 index5 boards, none shared
| Benchmark | Reka Flash 3 | Step 3.5 Flash | Leader |
|---|---|---|---|
| MMLU Pro (Artificial Analysis run) | 66.9% | Not measured | Only Reka Flash 3 measured |
| 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 13 boards here | |||
Web designNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Reka Flash 3 | 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 index02
| Benchmark | Reka Flash 3 | Step 3.5 Flash | Leader |
|---|---|---|---|
| IFBench | 30.4% | 66.5% | Step 3.5 Flash |
| Long context reasoning (AA-LCR) | 0.0% | 63.0% | Step 3.5 Flash |
| 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 27 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Reka Flash 3 | 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
Reka Flash 3 costs less
Repository review
50K input + 3K output tokens
Reka Flash 3 costs less
Agent loop
200K input + 10K output tokens
Reka Flash 3 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 | Reka Flash 3 | StepFun Step 3.5 Flash |
|---|---|---|
| Maker | Reka | StepFun |
| Weights | Open weights | Open weights |
| Released | March 12, 2025 | January 29, 2026 |
| Context window | 66K | 262K |
| Input $/Mtok | $0.10 | $0.10 |
| Output $/Mtok | $0.20 | $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 Reka Flash 3 better than Step 3.5 Flash for coding?
Neither model has a coding score yet, so the two cannot be ranked on coding. Pick Reka Flash 3 for output tokens 1.5x cheaper ($0.20 vs $0.30 per million) and work measured by Terminal-Bench Hard (Artificial Analysis run) or AA Intelligence Index, where it leads.
Which is cheaper, Reka Flash 3 or Step 3.5 Flash?
Reka Flash 3 costs $0.10 per million input tokens and $0.20 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, Reka Flash 3 or Step 3.5 Flash?
Step 3.5 Flash, with 262K tokens against 66K.
How many benchmarks is the Reka Flash 3 vs Step 3.5 Flash comparison based on?
7 benchmarks have a result for both models as of October 22, 2026. Reka Flash 3'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.