Neutrophil-to-Lymphocyte Ratio (NLR) Calculator with dNLR, PLR, SII and LMR
Calculate the neutrophil-to-lymphocyte ratio (NLR) from absolute counts or WBC and differential %, compare it with healthy-adult ranges, and get dNLR, PLR, SII and LMR.
How it works
NLR = absolute neutrophil count ÷ absolute lymphocyte count · from a differential: ANC = WBC × (neutrophils % + bands %), ALC = WBC × lymphocytes % · dNLR = ANC ÷ (WBC − ANC) · PLR = platelets ÷ ALC · SII = platelets × ANC ÷ ALC · LMR = ALC ÷ absolute monocytes
The neutrophil-to-lymphocyte ratio compares the two main white cell types in a routine complete blood count. Under physical stress, infection or inflammation, cortisol and catecholamines push neutrophils up and lymphocytes down within hours, so the ratio rises. Because it costs nothing beyond a standard blood count, NLR has been studied as a marker of severity or outcome in sepsis, heart disease, cancer, COVID-19 and many other conditions. Enter absolute counts, or the white cell count with the percentages from the differential; both give the same ratio. The result is compared with the healthy-adult range of 0.78–3.53 reported by Forget et al. (2017) and with Zahorec’s grading from normal (1–2) through a grey zone (2–3) to severe (11–17) and critical (above 17) inflammation and stress. In his 2021 review Zahorec treats values above 3.0 or below 0.7 as abnormal in adults and places the early-warning grey zone more precisely at 2.3–3.0. With platelets and monocytes the calculator also gives the derived NLR, platelet-to-lymphocyte ratio, systemic immune-inflammation index and lymphocyte-to-monocyte ratio, which appear alongside NLR in research. The Absolute Neutrophil Count calculator gives only the neutrophil count and neutropenia grade; this one relates neutrophils to lymphocytes.
Worked example
A blood count shows 5.2 ×10⁹/L neutrophils (5,200/µL) and 1.6 ×10⁹/L lymphocytes (1,600/µL). NLR = 5.2 ÷ 1.6 = 3.25. That is inside the healthy-adult range of 0.78–3.53 but in Zahorec’s “mild to moderate” band (3–7). With platelets of 250 ×10⁹/L and monocytes of 0.5 ×10⁹/L, PLR = 250 ÷ 1.6 = 156.3, SII = 250 × 5.2 ÷ 1.6 = 813 and LMR = 1.6 ÷ 0.5 = 3.20.
Sources: Forget P. et al., What is the normal value of the neutrophil-to-lymphocyte ratio? BMC Research Notes 2017 · Azab B. et al., Average values and racial differences of NLR in US adults (NHANES), PLOS ONE 2014 · Omni Calculator: NLR calculator (Zahorec grade table; 2,500 / 1,500 example) · The Metabolic Journal: NLR ranges (Zahorec 2021 thresholds; 4,000 / 2,000 example)
Frequently asked questions
What is a normal neutrophil-to-lymphocyte ratio?
In healthy adults NLR is usually between about 0.78 and 3.53, with an average around 1.65 in one study of 413 healthy workers. Zahorec describes 1–2 as normal, about 2.3–3 as a grey zone, and values above 3 or below 0.7 as abnormal. In a national US sample the average was 2.15, a little lower in Black adults (1.76).
What does a high NLR mean?
A high NLR means neutrophils are high relative to lymphocytes, a typical response to physical stress, bacterial infection, inflammation, surgery or trauma, and to steroid medicines. Values above about 3 are often reported as raised and above 6–9 in severe illness, but the cut-off that matters depends on the condition being studied. It does not diagnose any disease on its own.
How do I calculate NLR from percentages?
Divide the neutrophil percentage by the lymphocyte percentage: the white cell count cancels out. For example, 65% neutrophils and 22% lymphocytes give an NLR of 65 ÷ 22 = 2.95. Using absolute counts gives the same answer.
What is the difference between NLR and dNLR?
The derived NLR divides neutrophils by all other white cells (WBC − neutrophils) instead of by lymphocytes alone. It was developed for data sets that report only WBC and neutrophils, and it is always lower than NLR because the denominator also includes monocytes, eosinophils and basophils.
Can NLR be low?
Yes. An NLR below about 0.7–1 usually reflects a low neutrophil count (neutropenia, for example after chemotherapy or with some viral infections) or a high lymphocyte count. Check the absolute neutrophil count as well.
Related calculators
Educational tool, not a diagnosis. NLR is a non-specific marker: infection, surgery, stress, steroids, chemotherapy and many diseases change it, and published cut-offs differ by condition and lab. Interpret it with a clinician alongside the full blood count and your symptoms.