NLR Calculator — Neutrophil-to-Lymphocyte Ratio
The NLR divides the absolute neutrophil count by the absolute lymphocyte count from a routine blood test. It is a fast, low-cost marker for systemic inflammation, immune stress, and prognosis in infection, cancer, and cardiac disease.
cells/µL
cells/µL
Borderline — mildly elevated
- 1
Neutrophil count (ANC)
4,000 - 2
Lymphocyte count (ALC)
2,000 - 3
NLR = ANC ÷ ALC
4,000 ÷ 2,000 = 2
此計算機如何運作？
NLR = Absolute Neutrophil Count ÷ Absolute Lymphocyte Count, both from a standard CBC. Normal NLR is roughly 1–2; 3–5 suggests elevated inflammation; >5 is significantly elevated. It is a low-cost screening signal — not a standalone diagnosis — for systemic inflammation, infection, cancer prognosis, and surgical risk.
公式
How this is calculated
Neutrophils are the primary innate immune responders — they surge in acute infection, tissue injury, surgery, and physiological stress. Lymphocytes, the adaptive immune cells, often fall during the same states as cortisol and inflammatory cytokines drive their redistribution or apoptosis. The ratio of these two cell populations therefore amplifies a signal that neither count would reveal alone: when neutrophils rise and lymphocytes fall simultaneously the NLR climbs sharply.
The calculation is simply ANC divided by ALC, both read directly from the CBC differential. In adults at rest an NLR below 2 is generally considered normal; 2–3 is borderline and may reflect mild physiological variation; 3–5 suggests possible systemic inflammation or active disease; above 5 is significantly elevated and has been associated in published studies with worse outcomes in sepsis, solid-organ cancers, acute coronary syndrome, and major surgery.
Important limitations: the NLR is a screening tool, not a diagnostic test. It is influenced by corticosteroids, beta-blockers, smoking, physiological stress (exercise, trauma), and time of day. Published cut-offs vary between studies and populations, and a single elevated value is less informative than a trend. Clinical decisions require the full clinical picture alongside other investigations.
常見問題
In healthy adults the NLR typically falls between 1 and 2, with some references citing up to 3 as within normal variation. Values persistently above 3–5 warrant further evaluation; above 5 is significantly elevated in most clinical contexts. Age, comorbidities, and medications all shift the baseline.
The ANC mainly assesses neutropenia risk (dangerous when < 500–1,500 cells/µL). The NLR captures the balance between innate and adaptive immunity — an elevated ratio can be present even when both absolute counts are within their individual reference ranges, making it a more sensitive reflection of immune-inflammatory state.
No. A standard complete blood count (CBC) with differential — ordered routinely in most hospitals and clinics — provides the ANC and ALC directly. Most modern CBC reports list absolute cell counts; if yours shows only percentages, multiply the WBC by the neutrophil % and lymphocyte % (expressed as decimals) to get the absolute counts.
也稱為
TG we-Calculate Editorial Team. (2026). NLR Calculator — Neutrophil-to-Lymphocyte Ratio [Online calculator]. TG we-Calculate. https://we-calculate.com/zh-tw/calculator/nlr-calculator
TG we-Calculate Editorial Team. "NLR Calculator — Neutrophil-to-Lymphocyte Ratio." TG we-Calculate. 2026. https://we-calculate.com/zh-tw/calculator/nlr-calculator.
TG we-Calculate Editorial Team, "NLR Calculator — Neutrophil-to-Lymphocyte Ratio," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/zh-tw/calculator/nlr-calculator
@misc{wecalculate_nlr_calculator, title = {NLR Calculator — Neutrophil-to-Lymphocyte Ratio}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/zh-tw/calculator/nlr-calculator}}, year = {2026}, note = {TG we-Calculate} }
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