Compare · ModelsLive · 2 picked · head to head

GLM 5.1 vs GPT-5.5 Pro

Side by side · benchmarks, pricing, and signals you can act on.

Winner summary

Not enough overlapping benchmarks to declare a winner yet · GLM 5.1 · GPT-5.5 Pro are still filling in scores.

Hype vs Reality
GLM 5.1
#16 by perf·no signal
QUIET
GPT-5.5 Pro
#1 by perf·no signal
QUIET
Best value
36.9x better value than GPT-5.5 Pro
GLM 5.1
30.9 pts/$
$2.27/M
GPT-5.5 Pro
0.8 pts/$
$105.00/M
Vendor risk
z-ai logo
z-ai
private · undisclosed
Unknown
OpenAI logo
OpenAI
$840.0B·Tier 1
Medium risk
Pricing · per 1M tokens · projected $/mo at 10M tokens
ModelInputOutputContextProjected $/mo
z-ai logoGLM 5.1$1.05$3.50203K tokens (~101 books)$16.63
OpenAI logoGPT-5.5 Pro$30.00$180.00400K tokens (~200 books)$675.00