[whatmodel.sh](../../README.md) / Grok 4.20 (0309 reasoning)
# Grok 4.20 (0309 reasoning)
SpaceXAI (xAI) · released 2026-04 · closed weights
**score 70.3** ±0.8 · #77 of 732 · from 15 benchmark results across 6 sources
Score within the [LMArena (text)](https://whatmodel.sh/?set=lmarena-text&score=set) comparison set only.
## What it's good at
● marks Grok 4.20 (0309 reasoning) among every model on that task or test, worst to best.
task vs the others rank counts tests
agent tasks ▁▁▃▆█▄●▅▄▄▂▁ #116 of 313* 3.6% 1
coding ▁▁▁▃▅▇█▇●▄▃▁ #107 of 469* 11% 1
chat & writing ▁▁▁▃▆▄▆█▆▇●▃ #34 of 402* 6.1% 1
math ▁▁▃▅█▆▄█●▂▁▁ #57 of 431 46% 3
vision & documents ▁▁▂▂▁▃▄▂▆▇●▄ #44 of 153* 6.1% 2
agent tasks · #116 of 313 · 3.6% of its score
Trails [SmolLM3 3B](smollm3-3b.md), [Devstral 2 (2512)](devstral-2.md), [Nova 2 Pro (Preview)](nova-2-pro.md) here, though they rank lower overall.
test result vs the others in its run difficulty counts why
τ³-bench banking_knowledge (v1.0.… 18.0% ▃▃▂●·▆▃▂█▅▅▂ beats 5/25 very hard · avg 4.3% 3.6% at its level
coding · #107 of 469 · 11% of its score
Trails [Llama 3.1 Nemotron Ultra 253B v1](llama-3-1-nemotron-ultra-253b.md), [Nemotron Cascade 2 30B-A3B](nemotron-cascade-2-30b-a3b.md), [MiniMax-M2.1](minimax-m2-1.md) here, though they rank lower overall.
test result vs the others in its run difficulty counts why
Arena WebDev (Code Arena) 1374.1 ▁▁▃▂●█▃▆▅▅▁▂ beats 37/129 avg 981 11% sharp
chat & writing · #34 of 402 · 6.1% of its score
Beats [GPT-6 Sol](gpt-6-sol.md), [GPT-5.6 Terra](gpt-5-6-terra.md), [MiMo-V2.6-Flash (309B-A15B)](mimo-v2-6-flash.md) here, though they rank higher overall.
test result vs the others in its run difficulty counts why
LMArena (text) 1471.5 ▁▁▁▂▃▃▃▆▆▇●▃ beats 347/385 avg 1260 6.1% blunt
math · #57 of 431 · 46% of its score
Beats [Qwen3.6 Max Preview](qwen3-6-max-preview.md), [Claude Sonnet 4.6](claude-sonnet-4-6.md), [DeepSeek V4 Pro (Preview, Apr 2026)](deepseek-v4-pro-preview.md) here, though they rank higher overall. Trails [A.X K2 (688B-A33B)](ax-k2.md) here, though they rank lower overall.
test result vs the others in its run difficulty counts why
FrontierMath tiers 1–3 v2 44.9% ▂··▁▁▃▄●█▆▄▃ beats 30/86 very hard · avg 1.2% 29% sharp · at its level
FrontierMath tier 4 v2 17.1% ▁▂▁▂●▅▂▃▂▁▁▁ beats 18/67 very hard · avg 0.1% 15% sharp
OTIS mock AIME 2024–2025 92.2% ▃▃▄▃▃▃▇▇●▃▂▅ beats 152/197 very hard · avg 7.2% 1.8% sharp · noisy
vision & documents · #44 of 153 · 6.1% of its score
Beats [MiMo-V2.6-Pro](mimo-v2-6-pro.md), [MiMo-V2.6-Flash (309B-A15B)](mimo-v2-6-flash.md), [GPT-6 Luna](gpt-6-luna.md) here, though they rank higher overall. Trails [Qwen3.6 Flash](qwen3-6-flash.md), [Gemini 3.5 Flash-Lite](gemini-3-5-flash-lite.md), [Qwen3.6 Plus](qwen3-6-plus.md) here, though they rank lower overall.
test result vs the others in its run difficulty counts why
Arena vision (style controlled) 1255.4 ▁▁▂▂▂▂▃▄▅▅●▇ beats 111/152 avg 1061 4.0% blunt
Arena document (style controlled) 1439.4 ▁▁▃▃●▃▇█▅▇▄▅ beats 8/37 avg 1331 2.1% blunt
other tests (7)
test result vs the others in its run difficulty counts why
GPQA Diamond 89.3% ▁▁▁▁▂▄▆▄▅▇●▅ beats 168/211 hard · avg 39% 6.2% sharp
ARC-AGI-2 public evaluation set (… 63.6% █··▂▅▁▃▁▃·●▃ beats 21/24 very hard · avg 0.3% 5.3% sharp · at its level · noisy
Chess Puzzles (Epoch) 24.0% █▁▁▁▁▂▃●▃▂▁▁ beats 92/137 very hard · avg 5.8% 4.0% sharp · noisy
ARC-AGI-1 public evaluation set (… 95.5% ▁·▇▃▁·█▇▁·●▃ beats 23/27 very hard · avg 4.0% 3.7% sharp · at its level · noisy
The Token Games Elo (10-model puz… 1057.0 █··▄●··▄·▄·▄ beats 3/7 avg 822 3.2% typical
WildClawBench 19.3% ●·▅▅█·▅█▅▃▃▃ beats 0/17 very hard · avg 11% 3.0% at its level
SimpleQA Verified 30.2% ▁▁▃▂▃●▆▆█▄▂▅ beats 19/81 very hard · avg 8.0% 2.2% at its level
source results share of the score
Epoch AI 6 58% ▇▇▇▇▇▇▇
LMArena leaderboard dataset 4 23% ▇▇▇
ARC Prize Foundation model_baseline out… 2 9% ▇
τ²/τ³-bench leaderboard: Sierra's own e… 1 4% ▇
The Token Games: Evaluating Language Mo… 1 3% ▇
WildClawBench: A Benchmark for Real-Wor… 1 3% ▇
prior: pull toward the middle 0% ▇
weighted average = 70.3
Licences: Epoch AI ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · LMArena leaderboard dataset ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · ARC Prize Foundation model\_baseline outputs on ARC-AGI-1/2 public evaluation sets ([MIT](../../licenses/arcprize-model-baseline-outputs-MIT.txt)) · τ²/τ³-bench leaderboard: Sierra's own evaluation runs ([MIT](https://opensource.org/license/mit)) · The Token Games: Evaluating Language Model Reasoning with Puzzle Duels ([CC BY-SA 4.0](../../licenses/paper-2602.17831v2-CC-BY-SA-4.0.txt)) · WildClawBench: A Benchmark for Real-World ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/))
## How to run it
### Through an API
api (xAI) · $1.56/M blended · $1.25 in / $2.5 out per 1M tokens · [docs.x.ai](https://docs.x.ai/docs/models)
[price source](https://github.com/anomalyco/models.dev/blob/a668908cfe7073faa0363699486fc41a3ff52412/providers/xai/models/grok-4.20-0309-reasoning.toml): Standard base token rate from models.dev. Provider-specific tiers, long-context surcharges, caching and promotions may differ. · [context source](https://docs.x.ai/developers/models.md): xAI API context for grok-4.20-0309-reasoning as listed (1M) on the official models/pricing table; prompts from 200K tokens use long-context pricing. Observed 2026-09-25.
[interactive version](https://whatmodel.sh/model/grok-4-20) · [JSON](https://whatmodel.sh/api?format=json&all=1)