Born on January 21 — Aquarius or Capricorn?

Depending on the year you were born, Aquarius or Capricorn.

Computed across 86 years, 1950–2035.

The boundary between two signs is not fixed to a date. It is fixed to the moment the Sun crosses a point in the sky, and that moment drifts a little from year to year. So two people born on the same date in different years can have different signs.

Year by year

the sign changes during this day — 1951 · 1952 · 1955 · 1956 · 1959 · 1960 · 1963 · 1964 · 1967 · 1968 · 1971 · 1972 · 1975 · 1976 · 1979 · 1980 · 1983 · 1984 · 1988 · 1992 · 1996 · 2000 · 2004 · 2008 · 2012 · 2016

Where you were born changes the answer too

The Sun crosses the boundary at one single instant for the whole world — but the clock reading at that instant differs by country. Two people born at the same local hour, in different countries, can have different signs.

To know for certain

A date alone cannot settle a boundary day. The time and place of birth are needed to compute the sky at that exact moment.

This is an astronomical calculation, not a description of you. This page computes where the Sun was. It says nothing about your character or your future.