Human Cell and Microbiome Census Explorer

Bacteria (3.8 × 10¹³)

Erythrocytes (2.5 × 10¹³)

Other Human (0.5 × 10¹³)

Drag mouse/finger to stir cellular micro-flow

Live Census Ratio

1.27 : 1

Bacterial cells to Human cells

Bacteria: 55.9% Human: 44.1%

Total Bacteria: 38.0 Trillion

Total Human Cells: 30.0 Trillion

Bacterial Biomass: ~0.20 kg (0.29%)

Human Cell Mass: ~46.0 kg (65.7%)

Scientific Insight (Sender et al. 2016)

The 10:1 Myth Debunked: Luckey's 1972 estimate assumed 100 trillion gut bacteria based on rough 10¹¹ cells/g over 1 liter. Sender et al. measured the actual colon content (~0.4 L) showing ~38T bacteria and ~30T human cells (84% of which are enucleated RBCs).

Count vs Mass Paradox: While bacteria outnumber human cells ~1.3 to 1, an average bacterium weighs only ~1-5 picograms. Thus, your entire 38T microbiome weighs only ~200 grams, whereas muscle and fat account for ~75% of your cell mass!