Doubles in
5.3 yrs
Rule of 72: 5.1 yrs
How long does it take to double your money at 14%? Estimate it with the Rule of 72 and compare it with the exact value — with a growth curve and a live calculator. Illustrative only, not investment advice.
At 14%, money doubles in about 5.1 years (Rule of 72), or 5.29 years exactly.
Pick a starting amount and a target — the rate stays fixed at 14%. The estimate and the exact value update live.
Fixed rate: 14% per year. $10,000 grows to 2× its value.
Rule estimate (72, 114, 144 ÷ 14) versus the exact logarithmic value and the difference.
| Target | Rule | Estimate | Exact | Difference |
|---|---|---|---|---|
| Double | 72 | 5.1 yrs | 5.29 yrs | -0.15 |
| Triple | 114 | 8.1 yrs | 8.38 yrs | -0.24 |
| Quadruple | 144 | 10.3 yrs | 10.58 yrs | -0.29 |
What $1,000 to $100,000 becomes when doubled at 14% — and after how many years.
| Starting amount | Doubled | Doubles in |
|---|---|---|
| $1,000 | $2,000 | 5.3 yrs |
| $5,000 | $10,000 | 5.3 yrs |
| $10,000 | $20,000 | 5.3 yrs |
| $25,000 | $50,000 | 5.3 yrs |
| $100,000 | $200,000 | 5.3 yrs |
5.3 yrs
Rule of 72: 5.1 yrs
8.4 yrs
Exact, ln(3) ÷ ln(1 + r)
10.6 yrs
Exact, two doublings
17.6 yrs
Exact, ln(10) ÷ ln(1 + r)
The exact doubling time comes from ln(2) ÷ ln(1 + r). For small rates that is roughly 100 · ln(2) ≈ 69.3 — but 72 divides far more easily in your head (by 1, 2, 3, 4, 6, 8, 9, and 12). At 14%, the rule estimates 5.1 years versus 5.29 exactly. The rule is most accurate near 8%; at very low or very high rates the gap grows.
Every figure on this page is illustrative only and not investment advice — real returns vary and are never guaranteed. For your own rate, use the Rule of 72 calculator. Background: Investopedia — Rule of 72.
The Rule of 72 estimates it fast: 72 ÷ 14 ≈ 5.1 years. The exact formula ln(2) ÷ ln(1 + 14%) gives 5.29 years. For most rates the estimate and the exact value sit only a fraction of a year apart.
Use Rule of 114 for tripling (114 ÷ 14) and Rule of 144 for quadrupling (144 ÷ 14). Exactly, money triples at 14% after about 8.4 years and quadruples after about 10.6 years.
The exact doubling time is ln(2) ÷ ln(1 + r). For small rates this is roughly 100 · ln(2) ≈ 69.3 — but 72 divides cleanly in your head (by 1, 2, 3, 4, 6, 8, 9, 12). That convenience is why 72 became the standard shortcut.
At 14%, the rule estimates 5.1 years versus 5.29 exactly. It is most accurate near 8% and drifts a little at very low or very high rates — but as a mental shortcut it stays useful across the whole range.
Tenfold takes about 17.6 years at 14% exactly (ln(10) ÷ ln(1 + 14%)). A handy shortcut is the "Rule of 231": 231 ÷ 14 gives a similar estimate.
No. This page explains the math of doubling time at 14% and is not investment, tax, or legal advice. Real returns vary and are never guaranteed.
Run your own rate
The Rule of 72 calculator opens pre-filled with 14% and shows doubling, tripling, and exact times for any rate.