Castelli Risk Index I & II (TC/HDL, LDL/HDL)

Castelli Risk Index-I (total cholesterol / HDL) and Risk Index-II (LDL / HDL), all in mg/dL; higher ratios mark a more atherogenic profile (interpretation context-dependent).

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Total cholesterol
200 mg/dL
LDL cholesterol
130 mg/dL
HDL cholesterol
50 mg/dL

Result: Castelli Risk Index-I 4 (TC/HDL), Risk Index-II 2.6 (LDL/HDL) — higher ratios mark a more atherogenic profile; interpretation is context-dependent.

The tool opens with these values already filled in. Replace them with your own.

What the result means

value
Risk Index-I = TC/HDL, Risk Index-II = LDL/HDL (unitless). Higher marks a more atherogenic profile; desirable is roughly < 5 (I) and < 3 (II), no single universal cut-point.

What you enter

  • Total cholesterol
  • LDL cholesterol
  • HDL cholesterol
How this is calculated

Castelli WP, Abbott RD, McNamara PM. Summary estimates of cholesterol used to predict coronary heart disease. Circulation. 1983;67(4):730-734. Risk Index-I = total cholesterol / HDL-C; Risk Index-II = LDL-C / HDL-C. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.