CtrlAltDebrief

GLM 5.1 vs GLM 5.2

API pricing, context window and capabilities for GLM 5.1 and GLM 5.2, side by side. Prices are the cheapest serving route per 1M tokens, verified against LiteLLM and OpenRouter.

Verdict

computed from the published numbers

GLM 5.1 wins on price. GLM 5.2 wins on coding, on intelligence and on context window.

Price
GLM 5.1
Coding
GLM 5.2
Intelligence
GLM 5.2
Context window
GLM 5.2

Key takeaways

who wins on what, from the published numbers

GLM 5.1 wins

  • Cheaper input ($1.05 vs $1.40 /1M)
  • Cheaper output ($3.50 vs $4.40 /1M)
  • More serving providers (2 vs 1)
  • Supports prompt caching

GLM 5.2 wins

  • Larger context window (203K vs 262K)
  • Higher max output (128K vs 262K)
Cheaper overall
GLM 5.1
$1.05 + $3.50 /1M
Larger context
GLM 5.2
262K
More providers
GLM 5.1
2 providers

Pricing & specs

cheapest serving route · per 1M tokens
GLM 5.1GLM 5.2
Input $/1M$1.05 best$1.40
Output $/1M$3.50 best$4.40
Context window203K 262K best
Max output128K 262K best
Serving providers2 best1
Released2026-04-07 2026-06-13

Benchmarks

Artificial Analysis indices, side by side
GLM 5.1GLM 5.2
Intelligence40.2 51.1 best
Coding55.8 68.8 best
GPQA Diamond87% 89% best
Output speed91 t/s 200 t/s best
Latency (TTFT)10.49s 6.32s best

Cost calculator

choose a serving route for each side
Input tokens / month
Output tokens / month
GLM 5.1
via OpenRouter
$8.75
GLM 5.2
via Cloudflare
$11

Capabilities

feature support, side by side
FeatureGLM 5.1GLM 5.2
Vision——
Tool use✓✓
Reasoning✓✓
Audio——
Prompt caching✓—
Structured output——
Web search——

Related comparisons

Frequently asked questions

Which is cheaper, GLM 5.1 or GLM 5.2?
GLM 5.1 is cheaper for input ($1.05 vs $1.40 per 1M tokens). GLM 5.1 is cheaper for output ($3.50 vs $4.40 per 1M tokens).
What is the context window difference between GLM 5.1 and GLM 5.2?
GLM 5.1 has a 203K-token context window and GLM 5.2 has 262K tokens, so GLM 5.2 can take a larger prompt.
How do GLM 5.1 and GLM 5.2 compare on benchmarks?
On the tracked Artificial Analysis indices, GLM 5.2 leads on coding, and GLM 5.2 leads on intelligence.
Pricing verified against LiteLLM + OpenRouter + provider pages · refreshed daily

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