# DeepSeek-V3.1-Terminus vs Grok 4.20 (Non-Reasoning)

> Grok 4.20 (Non-Reasoning) is the stronger model overall, scoring 48.6 to 43.1 on the Noometry Index. DeepSeek-V3.1-Terminus costs 3.5× less per token, which makes it the better buy when Grok 4.20 (Non-Reasoning)'s lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/deepseek-v3-1-terminus-vs-grok-4-20
- Last updated: 2026-10-12
- Shared benchmarks: 14

## Summary

- They share 14 benchmarks with published results for both. DeepSeek-V3.1-Terminus scores higher in 0 categories and Grok 4.20 (Non-Reasoning) in 7 categories; 5 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.20 (Non-Reasoning) leads 52.3 to 26.4.
- The biggest single-benchmark swing is Kagi LLM Benchmark: 57.4% for DeepSeek-V3.1-Terminus and 75% for Grok 4.20 (Non-Reasoning).
- DeepSeek-V3.1-Terminus is cheaper at $0.27 / $1 per million input/output tokens, against $1.25 / $2.50 for Grok 4.20 (Non-Reasoning).
- Grok 4.20 (Non-Reasoning) accepts more context: 1M tokens versus 164K.
- DeepSeek-V3.1-Terminus has downloadable open weights; the other is API-only.

## Snapshot

| | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| Provider | DeepSeek | xAI |
| Noometry Index | 43.1 | 48.6 |
| Rank | 97 | 54 |
| Context | 164K | 1M |
| Input $/M | $0.27 | $1.25 |
| Output $/M | $1 | $2.50 |
| Weights | Open | Proprietary |

## Coding

- DeepSeek-V3.1-Terminus: 42.0 (#113)
- Grok 4.20 (Non-Reasoning): 42.1 (#112)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Coding | 1426 | 1459 |
| ALE-Bench | 745.17 | 1,150 |
| LMArena WebDev | — | 1375 |
| SciCode | 40.6% | — |
| WeirdML | — | 52.3% |

## Agentic & Tool Use

- DeepSeek-V3.1-Terminus: —
- Grok 4.20 (Non-Reasoning): 34.4 (#46)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| Terminal-Bench | — | 57.3% |
| τ²-bench Banking | — | 18% |
| LMArena Search | — | 1189 |
| Vending-Bench 2 | — | 4,663 |

## Reasoning

- DeepSeek-V3.1-Terminus: 26.4 (#133)
- Grok 4.20 (Non-Reasoning): 52.3 (#32)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| Kagi LLM Benchmark | 57.4% | 75% |
| LMArena Hard Prompts | 1426 | 1451 |
| DTBench | 81.3% | 90.1% |
| LMCA | 28.6% | 38.7% |
| ARC-AGI-2 | — | 65.1% |
| NYT Connections (extended) | — | 85.4% |
| ARC-AGI-1 | — | 89.5% |
| CritPt | 1.7% | — |
| Chess Puzzles | — | 24% |
| Thematic Generalization | — | 63.8% |
| Epoch Capabilities Index | — | 151.98 |
| ForecastBench | — | 61.4 |

## Math

- DeepSeek-V3.1-Terminus: 38.5 (#137)
- Grok 4.20 (Non-Reasoning): 48.2 (#65)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Math | 1402 | 1455 |
| FrontierMath (Tiers 1-3) | — | 44.9% |
| FrontierMath Tier 4 | — | 17.1% |
| OTIS Mock AIME 2024-2025 | — | 92.2% |
| ProofBench | — | 14% |

## Knowledge

- DeepSeek-V3.1-Terminus: —
- Grok 4.20 (Non-Reasoning): 52.8 (#60)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| GPQA Diamond | — | 89.3% |
| SimpleQA Verified | — | 30.2% |
| LMArena Expert | — | 1439 |

## Multimodal

- DeepSeek-V3.1-Terminus: —
- Grok 4.20 (Non-Reasoning): 33.3 (#98)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Vision | — | 1263 |
| Blueprint-Bench 2 | — | 0% |
| LMArena Document | — | 1416 |

## Multilingual

- DeepSeek-V3.1-Terminus: 52.1 (#92)
- Grok 4.20 (Non-Reasoning): 54.5 (#40)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Non-English | 1407 | 1441 |
| LMArena Russian | 1436 | 1458 |
| LMArena Chinese | — | 1481 |
| LMArena French | — | 1476 |
| LMArena German | — | 1465 |
| LMArena Japanese | — | 1449 |
| LMArena Korean | — | 1417 |
| LMArena Spanish | — | 1443 |

## Instruction Following

- DeepSeek-V3.1-Terminus: 74.0 (#106)
- Grok 4.20 (Non-Reasoning): 74.8 (#83)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Instruction Following | 1404 | 1420 |

## Long Context

- DeepSeek-V3.1-Terminus: 43.4 (#97)
- Grok 4.20 (Non-Reasoning): 45.5 (#34)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Longer Query | 1421 | 1437 |
| CL-bench | — | 22.2% |
| CL-bench Life | — | 11.9% |

## Writing & Preference

- DeepSeek-V3.1-Terminus: 61.0 (#92)
- Grok 4.20 (Non-Reasoning): 65.7 (#44)

| Benchmark | DeepSeek-V3.1-Terminus | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Text | 1419 | 1451 |
| LMArena Creative Writing | 1403 | 1438 |
| LMArena Multi-Turn | 1411 | 1456 |
| EQ-Bench Creative Writing | — | 1574 |

## FAQ

### Is DeepSeek-V3.1-Terminus better than Grok 4.20 (Non-Reasoning)?

Grok 4.20 (Non-Reasoning) is the stronger model overall, scoring 48.6 to 43.1 on the Noometry Index. DeepSeek-V3.1-Terminus costs 3.5× less per token, which makes it the better buy when Grok 4.20 (Non-Reasoning)'s lead doesn't matter for your workload.

### Which is cheaper, DeepSeek-V3.1-Terminus or Grok 4.20 (Non-Reasoning)?

DeepSeek-V3.1-Terminus is cheaper. It lists at $0.27 per million input tokens and $1 per million output tokens; Grok 4.20 (Non-Reasoning) lists at $1.25 and $2.50.

### Is DeepSeek-V3.1-Terminus or Grok 4.20 (Non-Reasoning) better for coding?

They score almost the same on coding (42.0 vs 42.1); test both on your own repository before choosing.

### Which has the bigger context window?

Grok 4.20 (Non-Reasoning) does, with 1M tokens against 164K.

### How many benchmarks do DeepSeek-V3.1-Terminus and Grok 4.20 (Non-Reasoning) share?

14 benchmarks have published results for both models. DeepSeek-V3.1-Terminus has 16 scored results on Noometry and Grok 4.20 (Non-Reasoning) has 46.