China / Identity numbers
Chinese ID Number Validator (身份证号码校验)
Check whether an 18-character mainland Chinese resident identity number is well formed: the check character, the birth date, and the province code, with the sex it records. Checks a list at once.
Chinese ID Number Validator (身份证号码校验): The number is a six-digit place code, an eight-digit birth date, a three-digit sequence whose last digit is odd for men and even for women, and a check character: the first 17 digits weighted 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2, summed modulo 11, and looked up as 1, 0, X, 9, 8, 7, 6, 5, 4, 3, 2. Results agreed with the python-stdnum library on 20,000 numbers. Runs 100% locally in your browser with zero server file uploads.
- Category
- Business & admin tools
- Runs
- In your browser
- Cost
- Free · no sign-up
- Availability
- Ready to use
Runs entirely in your browser
The 18th character is a check digit over the first 17, weighted 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 and taken modulo 11 (10 is written X). The number also holds the place of registration, the birth date, and, in the 17th digit, the sex. Only the format is checked, not whether the number was issued; nothing leaves your browser.
Reading a number
In 11010519491231002X, 110105 is a district of Beijing, 19491231 the birth date, 002 the sequence (2 is even, so a woman), and X the check character.
For Taiwan's numbers, see the Taiwan ID validator; for Japan's, the My Number validator.
What the check character catches
The weights are 2¹⁷ down to 2¹ modulo 11, so changing any single digit, or swapping two neighbouring digits, always changes the check character. A typing slip in one place is therefore always caught; two slips can occasionally cancel out.
How to use it
- Type or paste ID numbers, one per line.
- Read which are valid, with the province, birth date, and sex each holds.
- For one that fails, see the reason and the check character it should have.
Privacy & limitations
Numbers are checked in your browser and never sent anywhere. An identity number is personal data: check only numbers you are allowed to handle.
Related tools
Frequently asked questions
Does a valid result mean the number was issued?
No: only that it is correctly formed. Only the authorities can confirm that a number belongs to someone.
Why is the last character sometimes X?
When the calculation gives 10, which does not fit in one digit, the Roman numeral X is used.
Do the first six digits name a district?
They are the place of first registration, down to the county; the tool shows the province, because county codes have changed many times since the 1980s.
Free tool · runs in your browser · no account required