Absolute Neutrophil Count (ANC) Calculator with Neutropenia Grade

How it works

ANC = WBC × (% segmented neutrophils + % bands) ÷ 100 · cells/µL = ×10⁹/L × 1,000 · severity: ≥ 1,500 normal · 1,000–1,499 mild · 500–999 moderate · < 500 severe · < 100 profound · CTCAE v6.0: grade 1 < 1,500–1,000 · grade 2 < 1,000–500 · grade 3 < 500–100 · grade 4 < 100 · febrile neutropenia (IDSA): single temperature ≥ 38.3 °C, or ≥ 38.0 °C for 1 hour, with ANC < 500 or expected < 500 within 48 h

The total white cell count can look only modestly low while neutrophils, the cells that fight bacteria and fungi, have almost disappeared. The absolute neutrophil count (ANC) fixes that by multiplying the white count by the share of it that is neutrophils: mature segmented neutrophils plus bands. A WBC of 1.8 ×10⁹/L (1,800 cells/µL) with 28% segs and 4% bands gives 1,800 × 0.32 = 576 cells/µL. In adults an ANC of 1,500/µL or more is normal. Neutropenia is usually called mild from 1,000 to 1,499, moderate from 500 to 999 and severe below 500, with counts under 100 often called profound. Infection risk climbs steeply below 500 and with every day the count stays there. Oncology trials grade the same number with the NCI's Common Terminology Criteria for Adverse Events. CTCAE v6.0, released in 2025, shifted the neutrophil grades down one step (grade 1 is now below 1,500 to 1,000 and grade 4 is below 100), partly so that people with a naturally lower baseline count are not over-graded. The calculator shows both v6.0 and the older v5.0 grade because protocols written before 2026 still use v5.0. Fever changes the urgency. The IDSA definition of febrile neutropenia is a single oral temperature of 38.3 °C or more, or 38.0 °C or more sustained over an hour, with an ANC below 500/µL or expected to fall below 500 within 48 hours; CTCAE uses an ANC below 1,000/µL with the same temperatures. Febrile neutropenia is treated as an emergency, with cultures and empirical IV antibiotics within an hour.

Worked example

With the defaults: WBC 1.8 ×10⁹/L, 28% segmented neutrophils, 4% bands and a temperature of 38.4 °C. Neutrophil fraction = 28 + 4 = 32%. ANC = 1.8 × 32 ÷ 100 = 0.576 ×10⁹/L, shown as 0.58 ×10⁹/L (576 cells/µL). That is moderate neutropenia, CTCAE v6.0 grade 2 (v5.0 grade 3). 38.4 °C is above 38.3 °C, so there is fever with an ANC below 1,000/µL: the CTCAE definition of febrile neutropenia is met, and the IDSA definition is met too if the count is expected to fall below 500/µL within 48 hours (switch that on under More options).

Sources: Oncology Nursing Society: Clinical calculation huddle card, ANC (formula and worked example) · MSD Manual medical calculator: Absolute Neutrophil Count (WBC × (segs + bands)) · A paradigm shift in neutrophil adverse event grading: CTCAE v5 vs v6 neutrophil grades and febrile neutropenia (PMC, 2025) · NCI CTCAE v6.0 quick reference (febrile neutropenia definition) · Omni Calculator: ANC calculator (worked example 6,000 × 33% = 1,980)

Frequently asked questions