Claude Sonnet 4.5 vs GLM 5.3 FlashX

Price, context window & benchmark comparison

Anthropic

Claude Sonnet 4.5

Anthropic
$3.00 / $15.00
Input / Output · per 1M tokens
VS
Z.ai (Zhipu)

GLM 5.3 FlashX

Z.ai (Zhipu)
$0.37 / $1.25
Input / Output · per 1M tokens
Compare different models
Anthropic
Z.ai (Zhipu)
Verdict: GLM 5.3 FlashX is 10.2× cheaper than Claude Sonnet 4.5 on a typical 3:1 input/output mix. GLM 5.3 FlashX has the larger context window (1M vs 1M).
Claude Sonnet 4.5GLM 5.3 FlashX
Input price / 1M$3.00$0.37
Output price / 1M$15.00$1.25
Blended price (3:1)$6.00$0.59
Cached input / 1M$0.30$0.09
Context window1M1M
Max output64K131K
Intelligence index20.7
Coding index52.1
Providers1
Best provider uptime (30m)100.0%
Vision inputYesYes
ReasoningYesYes
Tool callingYesYes
Released2025-09-292026-09-18
Retirement

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FAQ

Which is cheaper, Claude Sonnet 4.5 or GLM 5.3 FlashX?

GLM 5.3 FlashX is 10.2× cheaper than Claude Sonnet 4.5 on a typical 3:1 input/output mix.

Claude Sonnet 4.5 vs GLM 5.3 FlashX: which has a bigger context window?

Claude Sonnet 4.5: 1,000,000 tokens. GLM 5.3 FlashX: 1,048,576 tokens.

How much would 1 million requests cost?

At 2,000 input + 500 output tokens per request: Claude Sonnet 4.5 ≈ $13,500, GLM 5.3 FlashX ≈ $1,365.

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