Year (Avg) to Day (yr to d)
Result
365.2425 Day
Formula
d = yr × 365.2425
1 yr = 365.2425 d, and 1 d = 0.002737907007 yr.
The second is the SI base unit, defined by a caesium-133 transition frequency. Minutes, hours, days and weeks are exact multiples. Month and year here are Gregorian averages: a year of 365.2425 days and a month of one twelfth of that (30.436875 days).
Worked examples
- 1 yr × 365.2425 = 365.2425 d
- 10 yr × 365.2425 = 3,652.425 d
- 100 yr × 365.2425 = 36,524.25 d
Common mistakes
- Calendar months run from 28 to 31 days, so "3 months" from a given date is not 3 × 30.44 days. Use a date calculator for deadlines.
- A 365-day year, a 365.25-day Julian year and the 365.2425-day Gregorian year differ; interest and astronomy calculations specify which one they use.
Year (Avg) to Day table
| Year (Avg) (yr) | Day (d) |
|---|---|
| 1 | 365.2425 |
| 2 | 730.485 |
| 5 | 1,826.2125 |
| 10 | 3,652.425 |
| 20 | 7,304.85 |
| 50 | 18,262.125 |
| 100 | 36,524.25 |
| 1,000 | 365,242.5 |
The units
- Year (Avg) (yr)
- 1 Year (Avg) = 31,556,952 Second.
- Day (d)
- 1 Day = 86,400 Second.
Sources for these factors
- The International System of Units (SI Brochure), 9th edition — BIPM
- Guide for the Use of the International System of Units (SP 811), Appendix B: conversion factors — NIST
Last reviewed against these sources. An automated check recomputes every factor from its definition on each build. How we check accuracy