Years required for population to double at current growth rate (2026)

Barbados is projected to lead the world in years required for population to double at current growth rate, recording 2,666 years in 2026, followed by Grenada (2,666 years) and San Marino (778.82 years). Trinidad and Tobago (686.28 years) and Jersey (672.96 years) close out the top 5. Next up, Belgium (558.99 years) and Saint Kitts and Nevis (517.27 years). France (505.95 years), Nepal (481.35 years), and Guernsey (471.53 years) round out the top ten. The gap across the top ten is wide: Barbados would have 5.7× the value of Guernsey (471.53 years). Five of the top ten are in Europe. Among these countries, Grenada is projected to see the largest year-over-year change at +184.6%.