Orbit
HomeDealsBlog
Resources
ToolsCancel HubSubscription DealsCompareNews
Get Started →
Savings calculator

Emergency Fund Calculator

Work out how much to save for a rainy day. Enter your essential monthly expenses to see your target fund, how much you still need, and how long it takes to get there. Free, no signup.

Free, no signupAny currency3, 6 or 12 months of cover
Your monthly essentials
Enter the costs you would still have to pay if your income stopped. The must-pay figure, not your total spend.
£
£
£
£
£
£
£
Months of cover
How much cover is right for you?
Pick the line that best fits your income. It sets a suggested number of months, which you can still change above.
Where you are now
What you have set aside for emergencies today.
£
What you can add to the fund each month.
£
Your target emergency fund
£12,000
£2,000 of essentials a month, times 6 months of cover.
Progress to your goal25%
Saved £3,000£9,000 to go
Gap to target
£9,000
Time to reach it
1y 11m
At £400 a month, you reach £12,000 around June 2028.
Target £12,0006m1y1.5y
Adding £400 a month gets you to your target.
Assumes fixed essentials and a steady contribution. A guide, not financial advice.
Simon Chadwick
Simon Chadwick
Founder, Orbit Money
Method: essential monthly expenses times months of cover, with situational guidanceUpdated: 16 July 2026Sources: MoneyHelper, MoneySmart, NerdWallet

What an emergency fund is

An emergency fund is money set aside for the unexpected: a job loss, a broken boiler, a car repair, a sudden drop in income. It is the buffer that keeps a bad month from turning into debt. The point is not to grow it, it is to have it ready the day you need it, sitting in an account you can reach quickly and kept apart from your everyday spending.

The size of that buffer is measured in months of essential expenses, not a round number plucked from the air. Work out what you would still have to pay if your income stopped, then decide how many months of that you want to cover. The calculator above does the arithmetic and shows how far along you are.

How much should I save in an emergency fund?

The widely used guide is three to six months of essential outgoings. UK guidance from MoneyHelper suggests that if you spend around £1,000 a month on things you cannot go without, you might aim for £3,000 to £6,000 in emergency savings. Australia’s MoneySmart points to a similar starting point of a few months of expenses, and US guidance such as NerdWallet uses the same three to six month rule of thumb.

The formula is simple: target fund = monthly essential expenses × months of cover. If your essentials come to £2,000 a month and you want six months of cover, your target is £12,000. Save £3,000 of it already and the gap is £9,000. Put £400 a month toward it and you close that gap in 23 months. The calculator works all of this out as you type, in your chosen currency.

How much cover is right for you?

Three to six months is the headline, but the right figure depends on how secure and predictable your income is. The less certain the income, the longer your buffer should last:

Pick the line that fits in the calculator and it sets a suggested number of months, which you can still change. These are widely recommended ranges rather than hard rules, so round up if a longer job search or a less predictable income would leave you exposed.

Where to keep your emergency fund

Keep it liquid and separate. An instant-access or easy-access savings account is the usual home: your money stays available within a day or two, it earns a little interest, and holding it apart from your current account makes it less tempting to spend. Avoid locking an emergency fund into investments or anything with a withdrawal penalty. The whole value of the fund is being able to reach it the moment something goes wrong.

How to use this calculator

  1. Pick your currency from the switcher at the top.
  2. Enter your essential monthly costs, the must-pay figure, not your total spend. Leave anything that doesn't apply blank.
  3. Choose 3, 6 or 12 months of cover, or set a custom number.
  4. Use the situation toggle to get a suggested number of months for your income type.
  5. Add what you've already saved and an optional monthly contribution to see your gap, progress and the time to reach your target.

Frequently asked questions

How much emergency fund do I need?
A common rule of thumb is three to six months of your essential living expenses. Add up the must-pay costs you would still face if your income stopped, rent or mortgage, utilities, food, insurance, transport and minimum debt payments, then multiply by the number of months you want to cover. If your monthly essentials are £2,000, six months of cover is £12,000. The right number depends on your situation: three months tends to be enough with two stable incomes, six months suits a single or main income, and nine to twelve months is often suggested for variable or self-employed income, or a sole earner with dependents.
Is 3 months enough for an emergency fund?
Three months of essential expenses is a reasonable starting point, and for some households it is enough. It works best when you have two secure incomes, so one wage can cover the essentials if the other stops for a while. If you rely on a single income, work in an unstable sector, are self-employed, or support dependents on your own, most guidance points to a larger buffer of six to twelve months. Three months is a floor to aim for first, then build from there.
What is the 3-6-9 rule for an emergency fund?
It is a simple way to scale your emergency fund to how secure your income is. Three months of essential expenses for stable, dual-income households; six months for a single or main income; and nine months or more for variable, self-employed or higher-risk income. The idea is that the less predictable your income, the longer your buffer should last. Some people extend it to twelve months as a sole earner with dependents. Use the situation toggle in the calculator above to set a suggested number of months, then adjust to fit your own comfort.
Is 5k a good emergency fund in the UK?
It depends on your essential outgoings. If you spend around £1,000 a month on the things you cannot go without, £5,000 covers roughly five months, which is close to the usual three to six month target. If your essentials are £2,000 a month, the same £5,000 covers only about two and a half months, so you would likely want to save more. Enter your own figures above to see how many months £5,000 would buy you.
Where should I keep my emergency fund?
Keep it somewhere safe, separate from your everyday account, and easy to reach within a day or two. An instant-access or easy-access savings account is the usual home: your money stays available, it earns some interest, and keeping it apart from your current account makes it less tempting to dip into. Avoid tying an emergency fund up in investments or anything with a withdrawal penalty, since the whole point is being able to reach it the moment you need it.
How do I build an emergency fund fast?
Set a target with the calculator, then automate a standing order into a separate savings account on payday so the money moves before you can spend it. Start with a first milestone of one month of essentials to build momentum, then push toward your full target. Redirect any windfalls, a tax refund, a bonus or a pay rise, straight into the fund. Cancelling forgotten subscriptions and trimming recurring costs frees up money each month that can go straight in, which is where a subscription tracker like Orbit helps.

Related tools

50/30/20 Budget Calculator
Split your income into needs, wants and savings so the fund keeps growing.
How Long Will My Money Last?
See how many months your savings would cover your spending.
Compound Interest Calculator
See how your savings grow once the fund is built.
Net Worth Calculator
The full picture: what you own minus what you owe.
Debt Payoff Calculator
Balance building a buffer with clearing costly debt.

More budgeting & savings calculators

Sinking Fund Calculator
Add the costs you can see coming, Christmas, car service, insurance, holidays, and see what to set aside each month for each goal, plus the total to budget.
Superannuation Calculator
Estimate your super balance at retirement from your salary and current balance, in today's dollars. 12% Super Guarantee.
Coast FIRE Calculator
Find your Coast FIRE number and see if you can stop saving and still retire on time. Works in USD, GBP, AUD, EUR and CAD.
Bill Split Calculator
Split a shared subscription, family plan or bill fairly between people. See the cost per person and how much you save vs paying alone.
Mortgage Overpayment Calculator
See how much interest you'd save and how many years you'd knock off your mortgage by overpaying each month or with a lump sum.
Monthly vs Annual Calculator
Compare monthly vs annual pricing, see your potential savings, and factor in promo discounts.

Build the fund by cutting what you forgot.

Orbit finds every subscription draining your account and puts them in one place, so the money you free up can go straight into your rainy-day fund.

Try Orbit free
Simon Chadwick
About the author
Simon Chadwick
Founder of Orbit Money

Simon is the founder of Orbit Money, a tool that helps people track subscriptions and recurring spend. He builds Orbit's free money calculators and writes about personal finance for UK and Australian readers.

More from Simon →
This tool is a guide, not financial advice.