GLM 5.3 FlashX vs GPT-5.5

Price, context window & benchmark comparison

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GLM 5.3 FlashX

Z.ai (Zhipu)
$0.37 / $1.25
Input / Output · per 1M tokens
VS
O

GPT-5.5

OpenAI
$5.00 / $30.00
Input / Output · per 1M tokens
Compare different models
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O
Verdict: GLM 5.3 FlashX is 19.1× cheaper than GPT-5.5 on a typical 3:1 input/output mix. GPT-5.5 has the larger context window (1.1M vs 1M).
GLM 5.3 FlashXGPT-5.5
Input price / 1M$0.37$5.00
Output price / 1M$1.25$30.00
Blended price (3:1)$0.59$11.25
Cached input / 1M$0.09$0.50
Context window1M1.1M
Max output131K128K
Intelligence index38.4
Coding index74.9
Providers1
Best provider uptime (30m)100.0%
Vision inputYesYes
ReasoningYesYes
Tool callingYesYes
Released2026-09-182026-04-24
Retirement

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FAQ

Which is cheaper, GLM 5.3 FlashX or GPT-5.5?

GLM 5.3 FlashX is 19.1× cheaper than GPT-5.5 on a typical 3:1 input/output mix.

GLM 5.3 FlashX vs GPT-5.5: which has a bigger context window?

GLM 5.3 FlashX: 1,048,576 tokens. GPT-5.5: 1,050,000 tokens.

How much would 1 million requests cost?

At 2,000 input + 500 output tokens per request: GLM 5.3 FlashX ≈ $1,365, GPT-5.5 ≈ $25,000.

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