Comparing 2 models

GPT-5.5 vs GLM 5.1

Facts first, then task-specific rankings. A highlighted cell is better only for that row, not universally.

metric
Model 1GPT-5.5
Model 2GLM 5.1
Best for
Chat & Roleplay (#1)
Translation (#1)
Provider
openai
z-ai
Context
1.1MBest
205K
Input / 1M
$5
$0.97Best
Output / 1M
$30
$3.04Best
Tool use
yesBest
yesBest
Vision
yesBest
Reasoning
yesBest
yesBest
Open-weight
yesBest
Released
Apr 23, 2026
Jan 20, 2025