GLM 5.3 Flash vs Grok 4.20 0309 Reasoning

Price, context window & benchmark comparison

Z.ai (Zhipu)

GLM 5.3 Flash

Z.ai (Zhipu)
$0.013 / $0.0168
Input / Output · per 1M tokens
VS
xAI

Grok 4.20 0309 Reasoning

xAI
$1.25 / $2.50
Input / Output · per 1M tokens
Compare different models
Z.ai (Zhipu)
xAI
Verdict: GLM 5.3 Flash is 112.0× cheaper than Grok 4.20 0309 Reasoning on a typical 3:1 input/output mix. GLM 5.3 Flash has the larger context window (1M vs 1M).
GLM 5.3 FlashGrok 4.20 0309 Reasoning
Input price / 1M$0.013$1.25
Output price / 1M$0.0168$2.50
Blended price (3:1)$0.014$1.56
Cached input / 1M$0.0119$0.20
Context window1M1M
Max output944K30K
Intelligence index27.8—
Coding index71.5—
Providers40—
Best provider uptime (30m)100.0%—
Vision inputYesYes
ReasoningYesYes
Tool callingYesYes
Released2026-08-262026-10-16
Retirement——

Cost calculator

FAQ

Which is cheaper, GLM 5.3 Flash or Grok 4.20 0309 Reasoning?

GLM 5.3 Flash is 112.0× cheaper than Grok 4.20 0309 Reasoning on a typical 3:1 input/output mix.

GLM 5.3 Flash vs Grok 4.20 0309 Reasoning: which has a bigger context window?

GLM 5.3 Flash: 1,048,576 tokens. Grok 4.20 0309 Reasoning: 1,000,000 tokens.

How much would 1 million requests cost?

At 2,000 input + 500 output tokens per request: GLM 5.3 Flash ≈ $34.40, Grok 4.20 0309 Reasoning ≈ $3,750.

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