Calculate what your investments and savings will be worth in the future.
%
years
Future Value
$144,573
Your initial investment of $10,000 plus regular contributions will grow to $144,573, earning $86,573 in interest.
Initial Investment$10,000
Total Contributions$58,000
Interest Earned$86,573
Future value is calculated using the formula FV = PV(1+i)^n + PMT×((1+i)^n−1)/i, where PV is present value, i is the periodic interest rate, n is the number of periods, and PMT is the periodic contribution.
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What is the Future Value Calculator?
Future value is the amount of money your current and periodic investments will accumulate to after earning returns over a set period. It combines the growth of your lump-sum initial investment (via compound interest) with the growth of regular deposits (contributions). Unlike simple savings tracking, it factors in interest earned on interest—the compound growth that turns £10,000 invested 20 years ago into tens of thousands today.
How it works
You enter your starting amount, annual interest or return rate, time horizon in years, and how much you contribute regularly (monthly or annually). The calculator applies the compound interest formula to both the initial sum and each contribution, then sums the future values of both streams to show your total wealth at the end. It also displays total interest earned and a breakdown of contributions vs. growth.
FV = PV(1+i)^n + PMT×((1+i)^n−1)/i
FV is the future value (what you'll have); PV is the present value (starting amount); i is the periodic interest rate (annual rate ÷ periods per year); n is the total number of periods (years × periods per year); PMT is the regular contribution per period.
Examples
Input
Result
Notes
Initial £10,000, Rate 6% p.a., Time 20 years, Monthly contribution £200
Future Value: £98,506 | Interest Earned: £48,006
Shows how small regular deposits (£200/month = £48,000 over 20 years) nearly double in value through compound growth.
Initial £5,000, Rate 5% p.a., Time 10 years, Monthly contribution £150
Future Value: £26,891 | Interest Earned: £6,891
Demonstrates that even modest contributions compound significantly—£6,891 earned just from interest over a decade.
Initial £50,000, Rate 7% p.a., Time 15 years, Annual contribution £5,000
Future Value: £219,324 | Interest Earned: £74,324
Larger initial investment and contributions compound to more than double—interest and growth exceed the total invested amount.
How to use the Future Value Calculator
Enter your initial lump-sum investment (the amount you're starting with today).
Input the annual interest or expected return rate as a percentage (e.g., 6% for savings, 8% for equity funds).
Specify the time horizon in years—how long you'll keep the money invested.
Choose your contribution frequency: monthly or annually.
Enter how much you'll contribute each period (e.g., £200 per month).
Click Calculate to see the future value, total contributions, and interest earned.
Benefits
Plan retirement or major life expenses by projecting your savings forward 10, 20, or 30 years.
See the impact of regular contributions—many people underestimate how £100–200 monthly adds up with compound growth.
Compare different scenarios instantly: more initial capital vs. higher monthly contributions; different return rates; shorter vs. longer time horizons.
Set realistic wealth-building targets—work backwards from a goal (e.g., 'I need £500,000 in 25 years') to see what contribution rate is needed.
Understand the true cost of delaying investment—starting 5 years later or using a 1% lower return rate has cascading effects.
Make informed decisions about savings vehicles (low-yield savings vs. bonds vs. equity funds) by testing different return assumptions.
Tips & common mistakes
Common mistakes
Using annual returns for savings accounts that compound monthly—monthly compounding yields slightly more, and the difference grows over decades.
Forgetting to adjust contribution amounts to the correct frequency—entering 200 for monthly when you meant annual rate (should be 2,400/12).
Assuming rates remain constant—real-world returns fluctuate, and inflation erodes purchasing power, so this is a baseline projection, not a guarantee.
Confusing future value with inflation-adjusted value—£100,000 in 20 years is worth far less in today's purchasing power if inflation averages 3% annually.
Tips
Test a baseline scenario (realistic rate, current contribution rate, your target horizon), then shift one variable at a time to see sensitivity—e.g., 'what if I increased contributions by £50?'
Use historical returns as a rough guide: UK savings 3–5%, bonds 4–6%, equity funds 7–10% long-term, property 3–5%. Be conservative in planning.
For retirement planning, calculate future value first, then estimate your spending needs, and subtract to see the shortfall (if any) you need to address.
If you have multiple savings pots (ISA, pension, savings account), run separate calculations and sum the results to see your total projected wealth.
Frequently asked questions
What interest rate should I use?
Use rates relevant to your savings vehicle: UK savings accounts typically offer 4–5% (though rates change), fixed-rate bonds 4–6%, investment funds 7–10% long-term (but with volatility), and pension plans vary widely. Conservative planning uses lower rates; optimistic assumes historical averages. Always run a range of scenarios.
Does contribution frequency (monthly vs. annual) make a big difference?
Yes, but mainly because of timing. Monthly contributions let you invest smaller amounts more often, which means more money compounding earlier. Over 20 years, £200 monthly outpaces £2,400 annually by thousands of pounds, even at the same return rate. The calculator accounts for this automatically.
Can I use this for a pension or retirement plan?
Absolutely. Use your expected annual contribution (e.g., employer pension contributions + your own), your estimated return (pensions typically assume 5–7% real returns), and your years until retirement. Subtract your expected spending needs from the future value to see if you're on track.
How do I account for inflation?
Calculate the nominal (pre-inflation) future value with this tool, then estimate inflation's impact separately. If inflation is 2.5% p.a. and your nominal future value is £100,000 over 20 years, the real (inflation-adjusted) value is roughly £60,000 in today's pounds. Alternatively, subtract inflation from your return rate—so a 6% return with 2.5% inflation nets 3.5% real growth.
What if I want to increase contributions over time (e.g., annual raises)?
This calculator assumes fixed contributions each period. For stepped increases, run multiple calculations: one for early years with a base contribution, another for later years with a higher contribution, then sum the future values. Advanced tools allow step-up rates, but manual scenarios often work just as well.
Is future value the same as compound interest?
Not exactly. Compound interest is the earnings mechanism (interest on interest); future value is what you end up with (initial + contributions + all earnings). This calculator blends both—it's compound interest applied to a savings plan with regular deposits, not just a lump sum.