[KongchangAI]
Unverified50% confidenceFactExact time

Credit card numbers have fixed prefixes by card network: Visa starts with 4, and Mastercard starts with 51–55

1
Sources
50%
Confidence
Long-term
Relevance
8/8/2026
First Seen

Sources

DataBlur：实时模糊屏幕敏感数据的本地化隐私保护工具

Related Claims

UnverifiedBank card numbers follow the Luhn algorithm checksum, with Visa starting with 4 and Mastercard starting with 51–5577% similar

Cite This Claim

Stable URI
https://kongchang.com/claim/712608
API
curl https://kongchang.com/api/v1/knowledge/claims/712608
MCP
get_claim(id=712608)