GPT-5.6 SolvsGrok 4.20 Beta

GPT-5.6 Sol
Grok 4.20 Beta
API pricing
Input price
$5.00$1.25
Output price
$30.00$2.50
Cached input price
$0.50$0.20
Cheapest input
$4.40Amazon Bedrock
Cheapest output
$22.00Amazon Bedrock
Benchmarks
BullshitBench v2
48%56%
ARC-AGI-2
92.5%53.3%
Benchmarks
Gray Swan IPI · k = 1
3.1%
Gray Swan IPI · k = 10
16.3%
Gray Swan IPI · k = 15
20%
ProgramBench
1%
SWE-Bench Verified
76.7%
DeepSWE 1.1
73%
Next.js Evals
77%
Supabase Evals · with skills
89.9%
Supabase Evals · no skills
75.4%
Frontier-Bench v0.1
34.4%
Terminal-Bench 4.0
37.27%
Terminal-Bench 2.1
88.8%
BU Bench
67%
BrowseComp
92.2%
GDPval-AA v2
1748
threejseval
1421
Overview
CompanyOpenAISpaceXAI
Release dateJun 26 2026Feb 17 2026
AccessProprietaryProprietary

Other comparisons

GPT-5.6 SolvsClaude Fable 5.1Grok 4.20 BetavsClaude Fable 5.1GPT-5.6 SolvsGemini 3.8 FlashGrok 4.20 BetavsGemini 3.8 FlashGPT-5.6 SolvsMuse Spark 1.3Grok 4.20 BetavsMuse Spark 1.3GPT-5.6 SolvsDeepSeek-V4.1-FlashGrok 4.20 BetavsDeepSeek-V4.1-FlashGPT-5.6 SolvsMistral Medium 3.5Grok 4.20 BetavsMistral Medium 3.5GPT-5.6 SolvsKimi K3Grok 4.20 BetavsKimi K3

Frequently asked questions

GPT-5.6 Sol and Grok 4.20 Beta are evenly matched across the 2 benchmarks they both report (BullshitBench v2, ARC-AGI-2). Grok 4.20 Beta is cheaper on both input and output: $1.25 vs $5.00 per million input tokens, and $2.50 vs $30.00 per million output tokens. Figures are base-tier rates. Grok 4.20 Beta shipped 129 days before GPT-5.6 Sol, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

On BullshitBench v2, Grok 4.20 Beta leads at 56% vs GPT-5.6 Sol at 48%. On ARC-AGI-2, GPT-5.6 Sol leads at 92.5% vs Grok 4.20 Beta at 53.3%.