Cat Age ⇄ Human Age

Chart-based mapping: 1→7, 2→13, 3→20, 4→26, 5→33, 6→40; then add 4 per cat year. Fractional ages use linear interpolation.

Mode
Switching modes resets inputs (prevents backfilling).
Cat age
Any field can be used; results update instantly.
Converted human age
Derived via chart + interpolation, expressed as Y/M/D (avg 12 mo/yr, 30.44 d/mo).
Step-by-step derivation
Enter an age to see the derivation…
References & Notes
  • Common chart summary: 1→7, 2→13, 3→20, 4→26, 5→33, 6→40; then +4 per cat year.
  • This is a guide, not a medical rule—individual cats vary.
  • Months assumed as 1/12 of a year; days ≈ 30.44 per month (365.25/12).

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