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John Mast, MD
NPI 1508807561 · Surgery Physician · Tracy, CA
John Mast, MD is a Surgery Physician provider in Tracy, CA (NPI 1508807561).
Provider details
- NPI number
- 1508807561
- Entity type
- Individual
- Primary specialty
- Surgery PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- G34146 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
Detailed profile(91/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
20 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
473 W Eaton Ave
Tracy, CA 95376-3420
Phone: (209) 833-3320
Street-level locationGet directions
Mailing address
600 Coffee Rd
Modesto, CA 95355-4201
Registry dates
- Enumerated
- 2006-06-09
- Last updated
- 2014-03-24
Frequently asked questions
- What is John Mast's NPI number?
- John Mast's National Provider Identifier (NPI) is 1508807561, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Mast's specialty?
- John Mast is listed in the NPPES registry with a primary specialty of Surgery Physician (Allopathic & Osteopathic Physicians).
- Where is John Mast located?
- John Mast's practice location on file with NPPES is 473 W Eaton Ave, Tracy, CA 95376-3420.
- What is John Mast's phone number?
- The practice phone number listed in the NPPES registry for John Mast is (209) 833-3320.
- Is John Mast's NPI active?
- Yes — John Mast's NPI (1508807561) is active in the NPPES registry as of the last update on 2014-03-24.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.