ZACHARY FOX
NPI 1255138020
Psychologist - Clinical Child & Adolescent in San Mateo, CA

NPI Status: Active since February 27, 2025

Contact Information

1900 S NORFOLK ST STE 205
SAN MATEO, CA
ZIP 94403
Phone: (650) 242-0179

NPI Profile Information
Primary Taxonomy
NPI Validation
Other Providers Same Location
Frequently Asked Questions

Individual
Male
Psychologist
Clinical Child & Adolescent

About ZACHARY FOX

This page provides the complete NPI Profile along with additional information for Zachary Fox, a provider established in San Mateo, California with a medical specialization in Psychologist, focusing in clinical child & adolescent . The healthcare provider is registered in the NPI registry with number 1255138020 assigned on February 2025. The practitioner's primary taxonomy code is 103TC2200X. The provider is registered as an individual and his NPI record was last updated one year ago.

NPI: 1255138020
Provider Name: ZACHARY FOX
Gender: Male
Entity Type: Individual
Location Address: 1900 S NORFOLK ST STE 205 SAN MATEO, CA 94403
Location Phone: (650) 242-0179
Mailing Address: 1900 S NORFOLK ST STE 205 SAN MATEO, CA 94403
Mailing Phone: (650) 242-0179
Is Sole Proprietor?: No
Enumeration Date: 02-27-2025
Last Update Date: 02-27-2025
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Specialty - Primary Taxonomy

The NPI enumerator requires providers to submit at least one taxonomy code. A taxonomy code is a unique 10-character code that describes the healthcare provider type, classification, and the area of specialization. There could be only one primary taxonomy code per NPI record. For individual NPIs the license data is associated to the taxonomy code.

Classification: Psychologist Clinical Child & Adolescent
Taxonomy Code: 103TC2200X
Type: Behavioral Health & Social Service Providers
License State: CA
Taxonomy Description: A psychologist who develops and applies scientific knowledge to the delivery of psychological services to infants, toddlers, children and adolescents within their social context. Of particular importance to the specialty of clinical child psychology is an understanding of the basic psychological needs of children and adolescents, and how the family and other social contexts influence the socio-emotional adjustment, cognitive development, behavioral adaptation and health status of children and adolescents.

NPI NPI Number Validation

How NPI Validation Works

The NPI validation process uses the ISO-standard Luhn algorithm, a mathematical "handshake", to ensure that a provider's 10-digit ID is authentic and free of common typing errors.

To verify the NPI 1255138020, we treat the final digit (0) as the Check Digit—the target answer we need to reach. The process begins by taking the first nine digits and adding a constant value of 24, which accounts for the "80840" prefix required for all U.S. health identifiers. We then double every other digit starting from the right and sum the individual digits of those results together. For this specific NPI, that total comes to 50. The final step is to find the difference between that total and the next multiple of ten (50 - 50 = 0).

Digit-by-digit view

Use the first nine digits for the calculation. Starting from the right, double every other digit. The last digit is the check digit and is not part of the calculation.

Pos 1

Doubled → 2

Pos 2

Unchanged

Pos 3

Doubled → 10 → 1 + 0

Pos 4

Unchanged

Pos 5

Doubled → 2

Pos 6

Unchanged

Pos 7

Doubled → 16 → 1 + 6

Pos 8

Unchanged

Pos 9

Doubled → 4

Check

Target digit

Regular digit Doubled digit Check digit

Step 1: Double every other digit from the right

Starting with the rightmost digit of the first nine digits, double every other value. If doubling creates a two-digit number, add those digits together.

1 → 2 5 → 10 → 1 1 → 2 8 → 16 → 7 2 → 4

Step 2: Add all digits plus the NPI constant

Add the transformed values, the unchanged digits, and the constant 24.

2 + 2 + 1 + 0 + 5 + 2 + 3 + 1 + 6 + 0 + 4 + 24 = 50

Step 3: Find the amount needed to reach the next multiple of 10

The next multiple of ten after 50 is 50. The difference is the calculated check digit.

50 - 50 = 0

This NPI is valid

The calculated check digit is 0, which matches the last digit of 1255138020.