See how savings grow with compounding, including regular contributions.
Added every month
Annual rate
Final balance
$17,175.24
$13,000.00 paid in, $4,175.24 interest
| Year | Paid in | interest | Balance |
|---|---|---|---|
| 1 | $2,200.00 | $79.05 | $2,279.05 |
| 2 | $3,400.00 | $223.53 | $3,623.53 |
| 3 | $4,600.00 | $436.81 | $5,036.81 |
| 4 | $5,800.00 | $722.38 | $6,522.38 |
| 5 | $7,000.00 | $1,083.97 | $8,083.97 |
| 6 | $8,200.00 | $1,525.44 | $9,725.44 |
| 7 | $9,400.00 | $2,050.90 | $11,450.90 |
| 8 | $10,600.00 | $2,664.64 | $13,264.64 |
| 9 | $11,800.00 | $3,371.17 | $15,171.17 |
| 10 | $13,000.00 | $4,175.24 | $17,175.24 |
What this assumes
A lump sum
£1,000 growing for 10 years
1000Monthly saving
Regular contributions add up
200Long horizon
Where compounding really shows
30The lump sum you begin with. Zero is fine if you are starting from nothing and only contributing.
Optional, but it usually dominates the outcome over long periods.
Compounding frequency matters less than people expect — the rate and the time matter far more.
Seeing contributions and interest separately shows exactly when compounding takes over, which a single final figure hides.
Regular deposits are compounded period by period rather than approximated, so the figure matches what a bank would calculate.
A projection at a constant rate. Real returns vary, and the tool says so rather than implying certainty.
Project the growth of a lump sum, a regular contribution, or both. Choose how often interest compounds — annually through to daily — and see the balance year by year, split into what you put in and what the interest earned. The year-by-year table is the useful part: it shows the point at which growth starts outpacing contributions, which is the entire argument for starting early. Results are projections based on a constant rate you supply, not a forecast.
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