Beam 1.0 501B A23B vs Step 5 Preview
Updated October 21, 2026. 26 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick Step 5 Preview for coding: it scores 71.4 on the Vibe Coding Index against 33.8 for Beam 1.0 501B A23B.
Pick Beam 1.0 501B A23B when output tokens cost 2.7x less, or when what matters is LMArena Text: math or LMArena Text: mathematical work, where it leads.
- Shared results
- 26
- Beam 1.0 501B A23B only
- 2
- Step 5 Preview only
- 35
- Like-for-like categories
- 5 of 9
Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.
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, four public coding benchmarks
Step 5 Preview
Step 5 Preview scores 71.4 against 33.8.
1 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
No call
Only Step 5 Preview has a AA Intelligence Index result, 43.7.
Directional only
Web design
Design Arena: websites
No call
Only Beam 1.0 501B A23B has a Design Arena: websites result, 1253.
Directional only
Long documents
Listed context window
No call
Both take 1.05M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Beam 1.0 501B A23B
Beam 1.0 501B A23B $0.0008, Step 5 Preview $0.0024 per turn.
List prices
At a glance
- Coding index
- Beam 1.0 501B A23B 33.8 from 1 benchmark, Step 5 Preview 71.4 from 2 benchmarks.
- Widest category
- Coding, 13.2 points apart on average over 5 shared benchmarks.
- Widest single gap
- LMArena WebDev: React: Beam 1.0 501B A23B 1443 against Step 5 Preview 1583, 23.4 points apart on a 0 to 100 scale.
- Output price
- Beam 1.0 501B A23B $1.00 against Step 5 Preview $2.70 per million output tokens, 2.7x 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 | Beam 1.0 501B A23B | Bars | Step 5 Preview | Ties |
|---|---|---|---|---|
| Coding | 0 | 5 | ||
| Reasoning | 0 | 3 | ||
| Math | 2 | 0 | ||
| Knowledge | 0 | 4 | ||
| General | 1 | 11 | ||
| All shared boards | 3 | 23 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index05
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 85.6% | Only Step 5 Preview measured |
| LMArena WebDev | 1437 | 1567 | Step 5 Preview |
| Terminal-Bench 4 (Vals AI) | Not measured | 31.8% | Only Step 5 Preview measured |
| Vibe Code Bench (Vals AI) | Not measured | 70.4% | Only Step 5 Preview measured |
| Code migration (Vals AI) | Not measured | 39.0% | Only Step 5 Preview measured |
| IOI (Vals AI) | Not measured | 38.1% | Only Step 5 Preview measured |
| SWE-bench Multimodal (Vals AI) | Not measured | 40.8% | Only Step 5 Preview measured |
| SciCode | Not measured | 58.9% | Only Step 5 Preview measured |
| LMArena Text: coding | 1473 | 1485 | Step 5 Preview |
| LMArena Text: software and IT | 1461 | 1473 | Step 5 Preview |
| LMArena WebDev: React | 1443 | 1583 | Step 5 Preview |
| LMArena WebDev: HTML | 1436 | 1556 | Step 5 Preview |
| LMArena WebDev: from an image | Not measured | 1550 | Only Step 5 Preview measured |
| Neither model has a result on the other 25 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| AA Intelligence Index | Not measured | 43.7 | Only Step 5 Preview measured |
| Neither model has a result on the other 1 board here | |||
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index11 boards, none shared
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench research | Not measured | 72.8% | Only Step 5 Preview measured |
| LiveBench browser | Not measured | 24.0% | Only Step 5 Preview measured |
| LiveBench long agentic | Not measured | 27.5% | Only Step 5 Preview measured |
| SREBench (Vals AI) | Not measured | 0.4% | Only Step 5 Preview measured |
| Finance Agent (Vals AI) | Not measured | 50.7% | Only Step 5 Preview measured |
| Tax Agent Bench (Vals AI) | Not measured | 27.3% | Only Step 5 Preview measured |
| Legal Research Bench (Vals AI) | Not measured | 40.4% | Only Step 5 Preview measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 57.1% | Only Step 5 Preview measured |
| BioMysteryBench (Vals AI) | Not measured | 67.4% | Only Step 5 Preview measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 2.9% | Only Step 5 Preview measured |
| Vals Science Index | Not measured | 29.6% | Only Step 5 Preview measured |
| Neither model has a result on the other 28 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index03
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench reasoning | Not measured | 83.8% | Only Step 5 Preview measured |
| MysteryMechanism (Vals AI) | Not measured | 18.5% | Only Step 5 Preview measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 46.5% | Only Step 5 Preview measured |
| LMArena Text: hard prompts | 1442 | 1461 | Step 5 Preview |
| LMArena Text: expert | 1447 | 1485 | Step 5 Preview |
| LMArena Text: hard prompts in English | 1451 | 1454 | Step 5 Preview |
| LMArena Vision: diagrams | Not measured | 1308 | Only Step 5 Preview measured |
| LMArena Vision: homework | Not measured | 1265 | Only Step 5 Preview measured |
| Neither model has a result on the other 13 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| ProofBench | Not measured | 42.0% | Only Step 5 Preview measured |
| LMArena Text: math | 1459 | 1458 | Beam 1.0 501B A23B |
| LMArena Text: mathematical work | 1475 | 1460 | Beam 1.0 501B A23B |
| Neither model has a result on the other 10 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| LMArena Text: science | 1430 | 1454 | Step 5 Preview |
| LMArena Text: medicine and healthcare | 1376 | 1439 | Step 5 Preview |
| LMArena Text: legal and government | 1433 | 1437 | Step 5 Preview |
| LMArena Text: business and finance | 1430 | 1435 | Step 5 Preview |
| Neither model has a result on the other 13 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index3 boards, none shared
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| Design Arena: websites | 1253 | Not measured | Only Beam 1.0 501B A23B measured |
| Design Arena: game dev | 1222 | Not measured | Only Beam 1.0 501B A23B measured |
| LiveBench design | Not measured | 76.9% | Only Step 5 Preview measured |
| Neither model has a result on the other 6 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index111
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | Leader |
|---|---|---|---|
| LiveBench data analysis | Not measured | 63.5% | Only Step 5 Preview measured |
| Public Benefits Bench (Vals AI) | Not measured | 58.1% | Only Step 5 Preview measured |
| Long context reasoning (AA-LCR) | Not measured | 88.3% | Only Step 5 Preview measured |
| LMArena Text | 1425 | 1440 | Step 5 Preview |
| LMArena Text: instruction following | 1430 | 1438 | Step 5 Preview |
| LMArena Text: creative writing | 1390 | 1409 | Step 5 Preview |
| LMArena Vision | Not measured | 1265 | Only Step 5 Preview measured |
| LMArena Text: English | 1436 | 1447 | Step 5 Preview |
| LMArena Text: non-English | 1413 | 1428 | Step 5 Preview |
| LMArena Text: Chinese | 1424 | 1500 | Step 5 Preview |
| LMArena Text: Japanese | Not measured | 1383 | Only Step 5 Preview measured |
| LMArena Text: French | 1461 | 1438 | Beam 1.0 501B A23B |
| LMArena Text: Spanish | Not measured | 1441 | Only Step 5 Preview measured |
| LMArena Text: Russian | 1412 | 1433 | Step 5 Preview |
| LMArena Text: multi-turn | 1414 | 1437 | Step 5 Preview |
| LMArena Text: longer queries | 1429 | 1449 | Step 5 Preview |
| LMArena Text: writing and language | 1400 | 1425 | Step 5 Preview |
| LMArena Text: entertainment and media | 1399 | 1412 | Step 5 Preview |
| LMArena Vision: English | Not measured | 1290 | Only Step 5 Preview measured |
| LMArena Vision: reading text | Not measured | 1282 | Only Step 5 Preview measured |
| Neither model has a result on the other 26 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Beam 1.0 501B A23B | Step 5 Preview | 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
Beam 1.0 501B A23B costs less
Repository review
50K input + 3K output tokens
Beam 1.0 501B A23B costs less
Agent loop
200K input + 10K output tokens
Beam 1.0 501B A23B 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 | Reflection Beam 1.0 501B A23B | StepFun Step 5 Preview |
|---|---|---|
| Maker | Reflection | StepFun |
| Weights | Open weights | Open weights |
| Released | October 16, 2026 | October 8, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $0.30 | $1.00 |
| Output $/Mtok | $1.00 | $2.70 |
| Coding index | 33.8 | 71.4 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Beam 1.0 501B A23B better than Step 5 Preview for coding?
Pick Step 5 Preview for coding: it scores 71.4 on the Vibe Coding Index against 33.8 for Beam 1.0 501B A23B. Pick Beam 1.0 501B A23B when output tokens cost 2.7x less, or when what matters is LMArena Text: math or LMArena Text: mathematical work, where it leads.
Which is cheaper, Beam 1.0 501B A23B or Step 5 Preview?
Beam 1.0 501B A23B costs $0.30 per million input tokens and $1.00 per million output tokens; Step 5 Preview costs $1.00 and $2.70. Cost per solved task is known for neither of them.
Which has the bigger context window, Beam 1.0 501B A23B or Step 5 Preview?
Neither: both take 1.05M tokens.
How many benchmarks is the Beam 1.0 501B A23B vs Step 5 Preview comparison based on?
26 benchmarks have a result for both models as of October 21, 2026. Beam 1.0 501B A23B's coding index rests on 1 independent benchmark and Step 5 Preview's on 2. Where only one model has a result, the page says so instead of naming a winner.