GLM 5.3 FlashX vs o3

Price, context window & benchmark comparison

Z

GLM 5.3 FlashX

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

o3

OpenAI
$2.00 / $8.00
Input / Output · per 1M tokens
Compare different models
Z
O
Verdict: GLM 5.3 FlashX is 5.9× cheaper than o3 on a typical 3:1 input/output mix. GLM 5.3 FlashX has the larger context window (1M vs 200K).
GLM 5.3 FlashXo3
Input price / 1M$0.37$2.00
Output price / 1M$1.25$8.00
Blended price (3:1)$0.59$3.50
Cached input / 1M$0.09$0.50
Context window1M200K
Max output131K100K
Intelligence index
Coding index
Providers1
Best provider uptime (30m)100.0%
Vision inputYesYes
ReasoningYesYes
Tool callingYesYes
Released2026-09-182025-04-16
Retirement

Cost calculator

FAQ

Which is cheaper, GLM 5.3 FlashX or o3?

GLM 5.3 FlashX is 5.9× cheaper than o3 on a typical 3:1 input/output mix.

GLM 5.3 FlashX vs o3: which has a bigger context window?

GLM 5.3 FlashX: 1,048,576 tokens. o3: 200,000 tokens.

How much would 1 million requests cost?

At 2,000 input + 500 output tokens per request: GLM 5.3 FlashX ≈ $1,365, o3 ≈ $8,000.

More comparisons