John Ryu, O.D.
NPI 1609946847 · Optometrist · Simi Valley, CA
Enrolled with Medicare as Practitioner - Optometry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
John Ryu, O.D. is a Optometrist provider in Simi Valley, CA (NPI 1609946847).
Provider details
- NPI number
- 1609946847
- Entity type
- Individual
- Primary specialty
- OptometristEye and Vision Services Providers
- Credential
- O.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- 11209T (CA)
Specialties & taxonomies
Eye and Vision Services Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 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
Mailing address
Registry dates
- Enumerated
- 2006-11-08
- Last updated
- 2024-07-15
- Certified
- 2024-07-15
Frequently asked questions
- What is John Ryu's NPI number?
- John Ryu's National Provider Identifier (NPI) is 1609946847, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Ryu's specialty?
- John Ryu is listed in the NPPES registry with a primary specialty of Optometrist (Eye and Vision Services Providers).
- Where is John Ryu located?
- John Ryu's practice location on file with NPPES is 690 E Los Angeles Ave, Simi Valley, CA 93065-1857.
- What is John Ryu's phone number?
- The practice phone number listed in the NPPES registry for John Ryu is (626) 376-3513.
- Does John Ryu accept Medicare?
- John Ryu is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is John Ryu's NPI active?
- Yes — John Ryu's NPI (1609946847) is active in the NPPES registry as of the last update on 2024-07-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.