GPT-5.6 Sol alternatives
Quick answer · Updated July 2026
The closest alternative to GPT-5.6 Sol is GPT-5.6 Luna — comparable intelligence (— vs —); for a cheaper option, Grok 4.5 runs $2.00/M vs $5.00/M; for more speed, Morph V3 Large hits 2.9k t/s; and the best open-weight substitute is GLM 5.2.
Closest match
Cheaper alternatives
grok-4.5
$2.00/M input · 53.8 intel
claude-sonnet-5
$2.00/M input · 53.4 intel
gpt-5.4
$2.50/M input · 51.4 intel
glm-5.2
$0.546/M input · 51.1 intel
gemini-3.5-flash
$1.50/M input · 50.2 intel
gemini-3.1-pro-preview
$2.00/M input · 46.5 intel
Faster alternatives
Open-source alternatives
glm-5.2
51.1 intel · open weights · 1.0M ctx
minimax-m3
44.4 intel · open weights · 1.0M ctx
deepseek-v4-pro
44.3 intel · open weights · 1.0M ctx
kimi-k2.6
44.2 intel · open weights · 262K ctx
mimo-v2.5-pro
42.2 intel · open weights · 1.0M ctx
kimi-k2.7-code
41.9 intel · open weights · 262K ctx
Frequently asked
What is the best alternative to GPT-5.6 Sol?
GPT-5.6 Luna is the closest alternative to GPT-5.6 Sol, with an Intelligence Index of — (GPT-5.6 Sol scores —) at $1.00 per million input tokens.
Is there a cheaper alternative to GPT-5.6 Sol?
Yes — Grok 4.5 costs $2.00 per million input tokens versus $5.00 for GPT-5.6 Sol, while staying within ~8 points of its Intelligence Index.
Is there an open-source alternative to GPT-5.6 Sol?
GLM 5.2 is the strongest open-weight alternative to GPT-5.6 Sol — downloadable from Hugging Face and self-hostable, scoring 51.1 on intelligence.