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John J Karl, FNP-C

Nurse Practitioner in Olympia Fields, IL · enumerated 2007.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1487701728

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Registry record

Entity type Individual (Type 1)
Name John J Karl
Credential FNP-C
Sex Male
Practice address 3700 W 203rd St Ste 302, Olympia Fields, IL, 60461
Phone (708) 679-2518
Fax (708) 679-2519
Enumeration date Jan 5, 2007
Last updated in NPPES Oct 5, 2023

Taxonomy & licenses

163WR0006X Registered Nurse First Assistant Nursing Service Providers · License 041-258664 (IL) Secondary
163WR0006X Registered Nurse First Assistant Nursing Service Providers · License 71009040A (IN) Secondary
363L00000X Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 28163347A (IN) Secondary
363L00000X Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 041258664 (IL) Secondary
363L00000X Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 71009040A (IN) Secondary
363LF0000X Family Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 209.019289 (IL) Secondary
363L00000X Nurse Practitioner Physician Assistants & Advanced Practice Nursing Providers · License 209019289 (IL) Primary

Other identifiers

Identifier Type State Issuer
209.019289 Other IL ADVANCE PRACTICE REGISTERED NURSE FNP-C

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What specialty is John Karl?
John Karl is registered in NPPES with the primary taxonomy of Nurse Practitioner. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-10-05.