SumLoft
BUILT FOR FINANCIAL CLARITY

Loan, Savings & Retirement Calculators
Plan more. Pay less. Build wealth.

Fast, private calculators for loan payoff, retirement, and savings goals.

Loan payoff calculator

See how extra payments shorten your payoff timeline.

Payoff dateApr 204610 years early
Interest saved$118,38339% less interest
Total interest$185,762vs $304,145 scheduled

Balance over time

Paying an extra $300 monthly can cut around 10 years from this loan.

Calculator categories

Loan payoff

Pay off debt faster

Retirement

Project your balance

Savings

Reach a goal on time

Popular tools

How we calculate your answers

1. You enter numbersYour real balances, rates, and timelines.
2. We apply the formulasStandard amortization and compound-growth math.
3. We model timeMonth by month, so extra payments and growth show up.
4. You get clarityEstimates for education, private by default. Nothing is stored.

Browse by topic

Pick a subject and every guide filed under it, counted and ready.

All walkthroughs

Money walkthrough

43 guides

Money worksheet

2 guides

START HERE

Popular guides to start with

The foundational walkthroughs most readers open first, from compounding to your first budget.

A jar filling with coins and a small plant growing beside a rising chart
Money walkthrough

Compound Interest Formula: The Power of Compound Interest

Compound interest formula explained: A = P(1 + r/n)^(nt) variable by variable, worked examples, continuous compounding, and the power of compound interest.

Read the guide
A person budgeting at a table with an open laptop and a paper notebook
Money walkthrough

How to Make a Budget (7 Steps That Actually Stick)

This worksheet builds a budget in seven steps: add up take-home pay, categorize spending, pick a method, set limits, save first, automate, and review monthly.

Read the guide
A person adding cash into a savings envelope while checking a savings balance on a phone
Money walkthrough

How to Build an Emergency Fund (6 Steps)

This worksheet builds an emergency fund in six steps: set a target, hit a starter goal, open the right account, automate the transfer, and replenish it after use.

Read the guide
A person tallying assets and debts on paper at a desk with a calculator, house keys, and a bank statement
Money walkthrough

How to Calculate Your Net Worth (Step by Step)

This walkthrough calculates your net worth in seven steps: list your assets, value them fairly, total your debts, subtract, and read what the number means.

Read the guide
A person in their early fifties relaxing on a sunlit porch, calm and financially secure
Money walkthrough

How Much Do I Need to Retire at 55? The Real Number

This walkthrough shows how much money you need to retire at 55: annual spending times a multiple, the bridge before Medicare, and the monthly saving by age.

Read the guide
A person mapping out retirement plans at a wooden desk with a calculator, notepad, and laptop in warm window light
Money worksheet

How to Calculate Your Retirement Number (5 Steps)

This worksheet walks you step by step through calculating your retirement number, from annual spending to a monthly savings target, without a salary mistake.

Read the guide
MONEY WALKTHROUGHS

Guides that show the math

Every number here comes with a plain-English walkthrough of the formula behind it. Newest first.

All walkthroughs
Two terracotta pots on a sunlit windowsill, a small seedling with a few leaves in the smaller pot and a taller leafy plant in the larger oneMoney worksheetLatest

IRA Contribution Deadline: How the Timing Works

This worksheet explains how the IRA contribution deadline works, the two-year window, why workplace plans stop earlier, and what to confirm with the IRS.

26 min walkthrough
A curved wooden footbridge with a plank deck and rail crossing calm water in heavy mist, with trees faintly visible on the far bankMoney walkthrough

What Is a Pension? How It Works vs a 401(k)

What is a pension? This explainer covers defined benefit plans, benefit formulas, vesting, survivor and lump sum elections, and pension versus 401(k).

31 min
An older couple walking together along a quiet tree-lined path in warm afternoon lightMoney walkthrough

How Long Will Retirement Savings Last? The Real Math

This walkthrough answers how long will retirement savings last: the withdrawal rate math, sequence of returns risk, and what actually moves the number.

32 min
Several labeled glass savings jars in a row on a shelf, each holding a different amount of coins, suggesting the different types of retirement accountsMoney walkthrough

Types of Retirement Accounts: The Differences, Explained

This explainer maps the types of retirement accounts: 401(k), 403(b), IRA, Roth, HSA, annuities, and how each differs from investment and savings accounts.

31 min
A wooden footbridge crossing calm water in misty light, the crossing an old 401(k) makes after a job changeMoney walkthrough

What Happens to Your 401(k) When You Leave a Job? 4 Options

This walkthrough answers what happens to your 401(k) when you leave a job: the four options, vesting, rollover mechanics, and what cashing out commonly costs.

30 min
A row of glass jars holding steadily more coins on a table, suggesting the birth-year schedule that sets the Social Security full retirement ageMoney walkthrough

What Is the Full Retirement Age for Social Security? By Year

This walkthrough answers what is the retirement age for Social Security: full retirement age by birth year, early claiming cuts, and delayed credit math.

31 min
Two open hands receiving a small stack of coins over a wooden table in warm light, suggesting an employer adding matching money to an employee's retirement savingsMoney walkthrough

What Is a 401(k) Match? How Employer Matching Works

This explainer covers what a 401(k) match is: how employer matching formulas work, vesting, true-ups, and the math that makes the match worth grabbing.

31 min
A footbridge connecting two banks of a calm stream in soft morning light, suggesting money moving from one account to anotherMoney walkthrough

Backdoor Roth IRA: How It Works (Step by Step)

This explainer covers the backdoor Roth IRA: how earners over the Roth income limit fund a Roth by contributing to a traditional IRA, then converting it.

27 min
A desk calendar, a stethoscope, stacked coins, and a piggy bank arranged together on a light surface in cool lightMoney walkthrough

HSA vs FSA: Key Differences (and Which to Pick)

This explainer compares HSA vs FSA: ownership, rollover, contribution limits, investing, eligibility, having both, and which account fits your situation.

34 min
HOW TO USE SUMLOFT

Tools that teach

A calculator you understand beats one you just trust.

How we build

Every calculator is paired with a guide that explains the formula and the assumptions, so the answer is legible, not magic.

How we make money

Some links to financial products are affiliate links, at no cost to you. The calculators stay neutral.

SumLoft is an educational tool. Every result is an illustrative estimate built on the assumptions you enter, not financial advice. Rates, tax rules, and contribution limits change, so confirm the current figures and talk to a qualified financial professional before acting on any number.

Get matched with a financial advisor

Tell us a little about your goals. We will connect you with fiduciary financial advisors who can review your situation.

We will connect you with fiduciary financial advisors. No spam.
Put this free compound growth calculator on your site

Free to use with attribution. Paste this where you want the tool to appear:

Publishers: embed this calculator free