Model comparison 2026

GLM 5.3 vs Grok 4.20

GLM 5.3
Z.AI · Frontier · Open weights
$1.50/1M · 1.0M ctx
Grok 4.20
xAI · Frontier · Proprietary
$1.63/1M · 2M ctx

Community vote

Pick a winner in each dimension. You can change your vote any time.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for money
How much capability you get per dollar
Reliability
Consistent results: fewer refusals, loops and format breaks

Specs and pricing side by side

Spec
GLM 5.3
Grok 4.20
Maker
Z.AI
xAI
Blended price / 1M
$1.50
$1.63
Input / output
$0.08 in · $4.80 out / 1M tokens
$1.25 in · $2.50 out / 1M tokens
Context window
1.0M
2M
Open weights
Yes
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
9.3
8.6
Agentic Ability
9.4
8.0
Speed
7.8
7.6
Value for money
9.0
8.5
Reliability
8.8
8.5

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: GLM 5.3 or Grok 4.20?

Updated 2026-10-13

Choose GLM 5.3 if you want open-weight coding agents that need near-frontier agentic ability. Choose Grok 4.20 if you want agents that genuinely need 2M tokens of context.

In our editorial scoring, GLM 5.3 leads in 5 of five dimensions (output quality, agentic ability, speed, value for money and reliability), while Grok 4.20 leads in 0. On price, GLM 5.3 runs about $1.50 per 1M tokens (blended) and is open-weight; Grok 4.20 is about $1.63 and proprietary.

Where GLM 5.3 falls short
  • Custom license with conditions for very large hosting providers
  • Reasoning cannot be turned off
Full GLM 5.3 breakdown →
Where Grok 4.20 falls short
  • Big context costs add up fast
  • Smaller ecosystem than GPT/Claude
Full Grok 4.20 breakdown →

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