LedgerLenspersonal-finance software, measured properly

Free tool · No signup · Updated August 11, 2026

Emergency Fund Calculator

“Three to six months” is not advice, it’s a shrug. This works out how many months your situation needs from the things that actually change the answer — then tells you the month you reach it at your current savings rate.

Runs entirely in your browser — nothing you type is sent anywhere

Which of these are true for you?
Your target
$0
Still to save
$0
Fully funded in

Your milestone ladder

A full fund is a long way off for most people, and that’s exactly why so many give up on it. The ladder matters more than the target: each rung removes a specific category of disaster, and the first two rungs do most of the work.

RungAmountWhat it buys youStatus

Milestones are based on your essential monthly spend, not your take-home pay — an emergency fund replaces your bills, not your lifestyle.

How the target is worked out

Everyone starts at 3 months. Each risk factor you ticked adds one month, because each one either raises the chance you need the fund or lengthens the time you’d be drawing on it. The result is capped at 8 months, because past that point money sitting in cash is usually losing more to inflation than it’s buying you in safety.

The “fully funded” date compounds your APY monthly, so it accounts for interest doing part of the work — at 4% on a five-figure balance that’s a real contribution, not a rounding error.

Where the money should sit

Two rules, and they’re boring on purpose. Same day or next day access, and no chance of being worth less than you put in. That means a high-yield savings account or a money market fund. Not stocks: the recessions that cost you your job are the same events that knock 20–30% off your portfolio, so you’d be forced to sell at the worst moment. Not a CD you can’t break without penalty, and not the account you pay bills from — a fund you can see next to your grocery money quietly becomes grocery money.

Keep the first $1,000 rung somewhere you can reach in an hour. The rest can sit in something that pays properly.

LedgerLens Zero-Based Budget Toolkit

This calculator tells you the target. The toolkit is how you free up the money to hit it.

Get the toolkit$19 one-time

Instant download link on your receipt. This is our own product, not an affiliate offer.

The mistake this calculator exists to catch

Most people who “can’t build an emergency fund” are actually building one and then spending it on things that were never emergencies: car registration, the annual insurance premium, Christmas, the vet visit that happens every year. Those are predictable irregular costs, and they belong in sinking funds — separate, named, funded monthly — not in the fund that’s meant to catch a job loss.

If your fund keeps resetting to zero, that’s the diagnosis, and it’s fixable in an afternoon: work out your real sinking-fund number here.

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Disclosure: LedgerLens is reader-supported. As of August 11, 2026 this page contains no affiliate links; if that changes, affected links will be individually labeled and this notice updated the same day. The $19 toolkit above is our own product and we are paid for it directly. This calculator is a planning tool, not financial advice, and it does not know your full situation.