Enter your measured platelet and lymphocyte counts (concentrations) from a CBC report to calculate the platelet/lymphocyte ratio.

Platelet/Lymphocyte Ratio Calculator

Enter platelet and lymphocyte counts to calculate the ratio.

Example formats: Platelets 150 ×103/µL = 150,000 per µL (or 150 ×109/L = 150,000 per µL). Lymphocytes 2.0 ×103/µL = 2,000 per µL (or 2.0 ×109/L = 2,000 per µL).

Medical disclaimer: This calculator is for educational purposes only and is not medical advice or a diagnostic tool. Use measured values from a laboratory CBC report. If your platelet or lymphocyte counts are abnormal or you have concerning symptoms (such as chest pain, shortness of breath, unusual bleeding/bruising, high fever, or severe weakness), seek medical care.

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Platelet/Lymphocyte Ratio Formula

The following formula is used to calculate the platelet/lymphocyte ratio for a given number of platelets and lymphocytes. 

R = P / L

Variables:

  • R is the platelet/lymphocyte ratio
  • P is the number of platelets
  • L is the number of lymphocytes

To calculate the platelet/lymphocyte ratio, divide the number of platelets by the number of lymphocytes.

What is a Platelet/Lymphocyte Ratio?

The platelet/lymphocyte ratio (PLR) is a calculated value derived from a complete blood count (CBC): platelet count divided by lymphocyte count. It has been studied as a non-specific marker that may reflect inflammation or physiologic stress in certain contexts. PLR can be influenced by many factors (including transient illness, medications, and underlying conditions), and it is not a standalone test to diagnose cardiovascular disease, infection, or cancer. Interpretation should be done by a clinician alongside symptoms, medical history, and other lab results (for patient-friendly guidance, check major academic medical centers or government health websites).

How to Calculate Platelet/Lymphocyte Ratio?

The following steps outline how to calculate the Platelet/Lymphocyte Ratio.

  1. First, determine the number of platelets (P).
  2. Next, determine the number of lymphocytes (L).
  3. Finally, calculate the Platelet/Lymphocyte Ratio using the formula R = P / L.
  4. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Number of platelets (P) = 150,000

Number of lymphocytes (L) = 5,000