How do I check if an NPI number is valid?

An NPI is valid when it has 10 digits and its last digit matches the Luhn check digit computed over 80840 plus the first nine digits. A valid check digit doesn't prove the NPI is assigned; the NPPES lookup does.

Where does the provider data come from?

The CMS National Plan and Provider Enumeration System (NPPES), which CMS publishes as public data.

NPI lookup

Check any 10-digit NPI: validate the check digit and look the provider up in the CMS NPPES registry. Free, no login.

Try:Never enter patient information.

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# Provider endpoints are coming soon. Check digit today:
npx @healthcare.dev/cli npi 1234567893

How it works

NPI lookup, step by step

01
Enter the 10-digit National Provider Identifier.
02
We check the Luhn check digit (prefix 80840) instantly.
03
If it's valid, we look it up in the public CMS NPPES registry and show the name, type, status, location and taxonomy codes.

FAQ

How do I check if an NPI number is valid?: An NPI is valid when it has 10 digits and its last digit matches the Luhn check digit computed over 80840 plus the first nine digits. A valid check digit doesn't prove the NPI is assigned; the NPPES lookup does.
Where does the provider data come from?: The CMS National Plan and Provider Enumeration System (NPPES), which CMS publishes as public data.