NPPES file of Aug 9, 2026

Internal Medicine Physician in California

17,696 NPPES records list internal medicine physician with a practice address in California, 45 per 100,000 residents, the 17th highest rate of 51. Los Angeles and San Francisco have the most; each record links to the provider's NPI and the California license search. Page 160 of 354.

CMS NPPES registry, file of Aug 9, 2026; 2023 Census estimates · NUCC 207R00000X · method

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

Los Angeles has the most, 1,423

  1. Los Angeles1,423
  2. San Francisco1,318
  3. San Diego961
  4. Sacramento601
  5. Oakland432

Internal Medicine Physician records in California

  1. Tom-Oliver Klein, MDChula Vista, CA 919101235161787
  2. William Klein, MDNewport Beach, CA 926631205834819
  3. Aurel Kleinerman, M.D., PH.D.Menlo Park, CA 940251427238385
  4. Mary Ellen Kleinhenz, MDSan Francisco, CA 941431912950890
  5. Fredrick Kleinsinger, MDOakland, CA 946111245380062
  6. Robert Klemens, M.D.Alpine, CA 919011912244856
  7. Jill Klessig, MDLos Angeles, CA 900951790705150
  8. Robert Klett, M.D.San Francisco, CA 941091639392541
  9. Leah Klinger, MDSan Francisco, CA 941151720166382
  10. Joel Klompus, M.D.San Francisco, CA 941151477665503
  11. Alexander Klonoff, M.D.Los Angeles, CA 900891538629936
  12. Missak Kltchian, MDLos Angeles, CA 900271255359840
  13. Brian Kluess, M.D.Palm Springs, CA 922641376593970
  14. David KnappSan Francisco, CA 941091467563833
  15. Alan Kneitel, MDSan Rafael, CA 949031417031584
  16. Sue Knight, MDSan Ramon, CA 945831619968443
  17. Kevin Knobel, MDModesto, CA 953551174573760
  18. Anca Knoepfler, M.D.Davis, CA 956161912961426
  19. Donald Knotts, MEDICAL DOCTORCastro Valley, CA 945461790858611
  20. Stephen Knox, MDOakland, CA 946091255439345
  21. Jennifer Knox Barleben, M.D.Newport Beach, CA 926631386896264
  22. Anthony Ko, MDOakland, CA 946111437237211
  23. David Ko, MDEncinitas, CA 920241689683690
  24. David Ko, MDRancho Mirage, CA 922701568405470
  25. Edward Ko, M.D.Garden Grove, CA 928401396911798
  26. Edward Ko, MDSan Francisco, CA 941331841364841
  27. Elizabeth KoLos Angeles, CA 900591811630916
  28. Elizabeth Ko, M.D.Los Angeles, CA 900661801189048
  29. Gemma Ko, M.D.Pico Rivera, CA 906601437167715
  30. Ryan Ko, MDFresno, CA 937201609207281
  31. Steven Ko, MDFontana, CA 923351194135780
  32. War War Ko, MDSacramento, CA 958171386207421
  33. Youjong Ko, MDLos Angeles, CA 900121508934027
  34. Young Ko, MDLancaster, CA 935341639277130
  35. Brent Kobashi, MDSan Francisco, CA 941431780851899
  36. Gary Kobayashi, M.D.Vista, CA 920831245303353
  37. Shuichi Kobayashi, M.D.Mountain View, CA 940401871509752
  38. Brian Kobilka, M.D.Stanford, CA 943051609910710
  39. Tong Kobilka, MDRedwood City, CA 940631639241482
  40. Marta Kochanska, M.D.San Francisco, CA 941431417156936
  41. Edward Kocharian, M.D.La Jolla, CA 920371790727139
  42. Robert Kocher, MDPalo Alto, CA 943041386030559
  43. Minas Kochumian, M.D.Northridge, CA 913251235322538
  44. Elizabeth Kocot, M.D.Belmont, CA 940021720009673
  45. William Kocsis, MDNapa, CA 945581225078280
  46. Ann Kodani, D.O.Santa Clara, CA 950511528276888
  47. Steven Koe, M.D.Newbury Park, CA 913201174517296
  48. Harold Koeffler, M.D.Los Angeles, CA 900481659309649
  49. Elizabeth Koehler, MDPalo Alto, CA 943041154501930
  50. Anthony Koerner, M.D.Pasadena, CA 911061487620357

Source: CMS NPPES, primary taxonomy 207R00000X: records by practice city and the list of records, file of Aug 9, 2026.

California ranks 17 of 51 per resident

  1. New Jersey50
  2. New Hampshire48
  3. Minnesota46
  4. California45
  5. Florida45
  6. Ohio45
  7. 50 states and D.C.44

Source: CMS NPPES, primary taxonomy 207R00000X by practice state, file of Aug 9, 2026; records per 100,000 residents, 2023 Census estimates.

79.5% of these records appear in a Medicare file, against 78.7% nationally

A Medicare file here is Part D prescribing (2024), a MIPS score (2023), an Open Payments record (2024) or Medicare group billing (CMS Doctors and Clinicians). A record outside them may still see patients: these files cover Medicare only.

  1. California79.5%
  2. United States78.7%

Internal Medicine Physician records in California, measured

  • In a Medicare file14,068 of 17,696 · 79.5% here, 78.7% nationally
  • In the CMS Doctors and Clinicians file11,077 · 62.6% here, 61.4% nationally
  • Not updated in five years or more10,832 · 61.2% here, 55.4% nationally
  • Median graduation year2004 · the 11,065 records with a school on file

Source: CMS NPPES, file of Aug 9, 2026 (primary taxonomy 207R00000X); CMS Medicare Part D Prescribers 2024, MIPS 2023, Open Payments 2024 and Doctors and Clinicians, matched by NPI.

What the count covers

17,696 NPPES records list internal medicine physician (207R00000X) as their primary taxonomy with a practice address in California: 45 per 100,000 residents against 44 nationally (50 states and D.C.). Los Angeles has 1,423 of them (8%).

A record is a registration a provider made and keeps up to date: it shows neither that the provider is licensed nor that they still practice there. The state's own license search is the check.

States with a similar number

  1. New York12,067
  2. Florida10,151
  3. Texas9,175
  4. Pennsylvania7,300

States with a similar rate per 100,000

  1. Minnesota45.9
  2. Ohio44.8
  3. New Hampshire48.0
  4. Maine42.8

The largest states

  1. New York12,067
  2. Florida10,151
  3. Texas9,175
  4. Pennsylvania7,300
  5. Illinois7,238

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy; 2023 Census population estimates. A registry record is not a license.

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.