GLM 5.1 vs Mercury 2

API pricing, context window and capabilities for GLM 5.1 and Mercury 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 coding, on intelligence and on context window. Mercury 2 wins on price.

Price
Mercury 2
Coding
GLM 5.1
Intelligence
GLM 5.1
Context window
GLM 5.1

Key takeaways

who wins on what, from the published numbers

GLM 5.1 wins

  • Larger context window (205K vs 128K)
  • Higher max output (131K vs 50K)
  • More serving providers (5 vs 2)
  • Has reasoning mode

Mercury 2 wins

  • Cheaper input ($1.05 vs $0.25 /1M)
  • Cheaper output ($3.50 vs $0.75 /1M)
Cheaper overall
Mercury 2
$0.25 + $0.75 /1M
Larger context
GLM 5.1
205K
More providers
GLM 5.1
5 providers

Pricing & specs

cheapest serving route · per 1M tokens
GLM 5.1Mercury 2
Input $/1M$1.05 $0.25 best
Output $/1M$3.50 $0.75 best
Context window205K best128K
Max output131K best50K
Serving providers5 best2
Released2026-04-07 2026-02-24

Benchmarks

Artificial Analysis indices, side by side
GLM 5.1Mercury 2
Intelligence41.0 best21.9
Coding55.8 best31.1
GPQA Diamond87% best77%
Output speed56 t/s 939 t/s best
Latency (TTFT)1.71s best3.44s

Cost calculator

choose a serving route for each side
Input tokens / month
Output tokens / month
GLM 5.1
via DeepInfra
$8.75
Mercury 2
via Inception
$2.00

Capabilities

feature support, side by side
FeatureGLM 5.1Mercury 2
Vision
Tool use
Reasoning
Audio
Prompt caching
Structured output
Web search

Related comparisons

Frequently asked questions

Which is cheaper, GLM 5.1 or Mercury 2?
Mercury 2 is cheaper for input ($1.05 vs $0.25 per 1M tokens). Mercury 2 is cheaper for output ($3.50 vs $0.75 per 1M tokens).
What is the context window difference between GLM 5.1 and Mercury 2?
GLM 5.1 has a 205K-token context window and Mercury 2 has 128K tokens, so GLM 5.1 can take a larger prompt.
How do GLM 5.1 and Mercury 2 compare on benchmarks?
On the tracked Artificial Analysis indices, GLM 5.1 leads on coding, and GLM 5.1 leads on intelligence.
Pricing verified against LiteLLM + OpenRouter + provider pages · refreshed daily

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