ISA Calculator
Estimate how your tax-free ISA savings could grow over time.
Use calculator →Work out how long it could take to reach a savings target, how much you still need, and how much interest could help along the way.
Enter your target, current savings and monthly saving. The calculator updates automatically as you change the inputs.
The time-to-goal result estimates how long it could take for your current savings, monthly deposits and interest to reach your target.
The monthly-needed figure works backwards from your target deadline. It shows the approximate monthly saving required to hit the goal by then.
Planning note: interest rates can change, so treat the result as an estimate rather than a guarantee.
Compare savings and ISA options if your current monthly saving plan is on track but you want a better place to hold the money.
A savings goal is simply a target amount with a plan attached. The plan usually includes what you already have, what you can add each month, and when you want to reach the target.
For short-term goals, keeping the money stable is usually more important than chasing high returns. For longer-term goals, inflation and interest become more important because the real value of money changes over time.
For an emergency fund, many people focus on essential monthly expenses rather than a fixed round number. For a house deposit or large purchase, the deadline may be more important because prices can change while you save.
The calculator compounds the balance monthly until the target is reached.
monthly_rate = annual_rate / 100 / 12
balance = current_savings
repeat each month:
balance = balance × (1 + monthly_rate) + monthly_saving
months_to_goal = first month where balance >= targetIf the interest rate is 0%, the calculator uses a simple savings gap divided by monthly saving.
Subtract your current savings from your target, then divide the gap by your monthly saving. If interest is included, the calculator compounds the balance monthly until it reaches the target.
That depends on your target amount, current savings and deadline. The shorter the deadline, the more you need to save each month.
Include interest if your savings account pays it, but use a cautious rate because savings rates can change.
If your current savings already meet or exceed the target, the calculator shows the goal as reached.
Yes. Choose emergency fund as the goal type, or use the dedicated Emergency Fund Calculator for a more expense-based target.
These glossary pages explain the main concepts behind saving, interest and real spending power.