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MONEY WALKTHROUGHS

Guides that show the math

Every number on SumLoft comes with a plain-English walkthrough of the formula behind it. Loan payoff, retirement, saving, and compound interest. Newest first.

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457(b) Plan Distribution Rules, Limits, and Withdrawals

This explainer covers 457(b) plan distribution rules, who sponsors the plan, the governmental split, deferral limits, and the separation-from-service quirk.

32 min walkthrough
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How to Fill Out a W-4 So You Don't Owe in April (7 Steps)

This worksheet shows how a W-4 turns into a withholding amount, why a second job under-withholds by default, and how to fix a refund or a bill that is wrong.

40 min
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How to Max Out Your 401(k) Before Year End (6 Steps)

This worksheet backs out the per-paycheck percentage that maxes out a 401(k) before year end, counting the pay periods left and guarding the employer match.

39 min
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Retirement Withdrawal Order: Which Account to Tap First

This walkthrough covers retirement withdrawal order: why taxable money usually goes first, when bracket filling reverses it, and how RMDs override the plan.

32 min
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What Is a CD? How Certificates of Deposit Work

This explainer covers how a certificate of deposit works, the term for rate trade, early withdrawal penalties in months of interest, CD ladders and variants.

38 min
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How to Manage Money With a Partner

This walkthrough sets up money with a partner in nine steps: the first conversation, joint or separate accounts, a proportional bill split, a solo-spend rule.

42 min
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Retirement Account Beneficiary Rules Explained

This explainer covers retirement account beneficiary rules: why the form outranks your will, primary versus contingent, per stirpes, trusts, and reviews.

35 min
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What Are I Bonds? How Do I Bonds Work

This explainer covers how I bonds work: the two-part rate built from a fixed piece and a resetting inflation piece, the lock-up and forfeit, and who it suits.

40 min
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Healthcare Costs in Retirement: How to Plan

This walkthrough prices healthcare costs in retirement across three separate phases: the pre-Medicare bridge, the Medicare years, and long-term care risk.

34 min
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Taxable Account vs Retirement Account: Where to Save

This comparison covers taxable vs retirement account order: what the match is worth, what tax drag really costs, and the four cases where a brokerage wins.

33 min
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What Is a Target Date Fund? How It Works and the Glide Path

Target date fund explained: what it is, how these funds work, how the glide path shifts stocks into bonds, the to versus through split, and the fees inside.

38 min
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How Much Social Security Will I Get? How to Estimate

This walkthrough shows how much Social Security you will get: the earnings formula, bend points, the 35 year rule, and how to read your own SSA statement.

37 min
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How to Do a Roth Conversion (and When It Pays)

This walkthrough covers how to do a Roth conversion: the mechanics, the rate now versus rate later test, the pro-rata trap, and paying the tax from outside.

32 min
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Required Minimum Distributions (RMDs), Including Roth IRAs

Required minimum distributions explained, including whether Roth IRAs have RMDs, how the calculation works, the aggregation and timing traps, and the penalty.

36 min
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The 50/30/20 Budget Rule: How to Actually Use It

This breakdown puts real numbers on 50/30/20: what each bucket holds, gross versus net, why 50 percent needs often fails, and how to adapt it to real costs.

31 min
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UTMA vs 529 Plan: Which Fits Your Savings Goal

This explainer compares UTMA vs 529 plan: who legally owns the money, how each is taxed, the aid math, what the money can buy, and when using both fits.

32 min
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What Is a Fiduciary Financial Advisor?

This walkthrough explains what a fiduciary financial advisor owes you, how each fee model shapes advice, and the questions to ask before you hire anyone.

34 min
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What Is a Solo 401(k)? Rules and Contribution Limits

This explainer covers what a Solo 401(k) is: who qualifies, the two-hat contribution structure, the Roth and loan options, deadlines, and the SEP IRA math.

33 min
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Do You Need a Financial Advisor for a Roth IRA?

This walkthrough explains whether you need a financial advisor for a Roth IRA, what one adds, fee models against the DIY route, and when advice pays off.

27 min
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IRA Contribution Deadline: Roth, Traditional, and Extensions

This worksheet covers the IRA contribution deadline, the Roth IRA deadline, the two-year window, when contributions reset, and whether an extension moves it.

35 min
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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
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How Long Will My Retirement Savings Last? The Real Math

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

32 min
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Types of Retirement Accounts: The Differences, Explained

Types of retirement accounts differ on tax timing, contribution limits, and access rules: 401(k), 403(b), IRA, Roth, HSA, annuities, and pensions, mapped.

32 min
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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
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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
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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
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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
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What Is an Annuity? (Types & How They Work)

What is an annuity? This explainer covers the insurance contract that pays retirement income, its main types, phases, fees, riders, pros, and the honest cons.

38 min
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What Is Inflation? (and How to Protect Your Money)

This explainer covers what inflation is, how the CPI measures it, what causes it, why some inflation is normal, how it erodes cash, and ways to protect money.

32 min
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What Is a Money Market Account? (MMA Guide)

This explainer covers what a money market account is, how it works, MMA versus high-yield savings and CDs, and the crucial money market fund distinction.

36 min
A calculator, a coffee cup, and a stack of printed statements on a sunlit wooden desk, the paperwork side of planning retirement contributionsMoney walkthrough

What Is a SEP IRA? (Self-Employed Retirement)

This explainer covers what a SEP IRA is: the self-employed retirement plan funded by employer contributions, its limits, tax breaks, deadlines, and rivals.

30 min
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Sinking Fund: What It Is, Examples, and Monthly Math

A sinking fund saves gradually for one planned expense. This walkthrough covers what it is, the categories, worked examples, the math, and where to keep it.

33 min
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Do You Need a Financial Advisor for Your 401k?

This walkthrough explains whether you need a financial advisor for your 401k, what one does, fee models versus target-date DIY funds, and when it pays off.

32 min
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Roth IRA Growth: How Much It Can Grow

Roth IRA growth explained: how tax-free compounding, contributions, time, and return rate turn steady saving into a big balance, plus a growth calculator.

26 min
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403(b) vs 401(k): What's the Difference?

403(b) vs 401(k) differ mainly in who offers them: investment menus, fees, ERISA coverage, catch-up rules, and contribution limits, all compared here.

32 min
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IRA vs 401(k): How to Choose (or Use Both)

This explainer breaks down IRA vs 401(k): how an individual account and an employer plan differ, why the match comes first, and the order to use both.

32 min
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Roth IRA vs Traditional IRA: How to Choose

This explainer compares Roth IRA vs traditional IRA: tax now versus tax later, income limits, RMDs, early withdrawals, and who each account really suits.

31 min
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What Is an HSA? Rules, Eligible Items, and Perks

This explainer covers what an HSA is, the HDHP eligibility rule, the triple tax advantage, HSA-eligible items, and how an HSA stacks up against an FSA.

33 min
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How to Do a Financial Checkup (8-Point Review)

This checkup runs a financial review in eight points: net worth, budget vs actual, emergency fund, debt, retirement, insurance, credit and goals, in an hour.

31 min
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How to Set Financial Goals That Work (7 Steps)

This worksheet sets financial goals in seven steps: list what you want, make each SMART, sort by time horizon, fund the essentials, then automate and review.

28 min
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401(k) Withdrawals: Rules, Age, and Taxes Explained

This explainer covers 401(k) withdrawal rules by mechanism: the five ways money leaves a plan, what withholding does, and why a loan is not a withdrawal.

40 min
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Checking vs Savings Account: Differences and When to Use Each

This explainer breaks down checking vs savings: what each is for, how they differ on interest and access, whether you need both, and how to use them together.

27 min
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Roth IRA Contribution Withdrawal Rules (and Multiple IRAs)

This explainer covers Roth IRA contribution withdrawal rules: why contributions come out anytime, when earnings are taxed, and how the five-year rule works.

35 min
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What Is a High-Yield Savings Account? How They Work and Why

This explainer covers what a high-yield savings account is, how high-yield savings accounts work, APY vs interest rate, and the real benefit of the account.

29 min
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How to Calculate Net Worth: The Step-by-Step Formula

How to calculate net worth, step by step: list what you own, value each line fairly, total what you owe, subtract, and read the result on a sample statement.

43 min
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How to Catch Up on Retirement Savings (7 Steps)

This worksheet shows how to catch up on retirement savings in 7 steps, from sizing the gap to using catch-up contributions, so a late start still lands one.

28 min
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How to Roll Over a 401(k) (6 Steps, No Penalty)

This worksheet walks you through rolling over a 401(k) in 6 steps, using a direct trustee-to-trustee transfer so you avoid the costly cash-out mistake.

28 min
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How to Build an Emergency Fund (6 Steps)

How to build 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.

26 min
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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.

27 min
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How to Start a Roth IRA: Open One in 6 Steps

This worksheet covers how to start a Roth IRA in six steps: the eligibility gate, where to set one up, funding, investing the cash, automating, and the rules.

53 min
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How to Calculate Your Retirement Number: The Formula (5 Steps)

This worksheet gives you the formula for retirement: your number step by step, from annual spending to a monthly savings target, without a salary mistake.

26 min
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How Much Should I Have in My 401(k) by Age?

This walkthrough answers how much should I have in my 401(k) by age: the salary-multiple guideposts for 30, 40, and 50, average versus recommended balances.

28 min
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How Much Do You Need to Retire at 65?

This walkthrough answers how much do you need to retire at 65: the safe withdrawal math, the Social Security boost, and whether 1 million is enough at 65.

26 min
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Can You Retire at 60 with $500k?

This walkthrough answers whether you can retire at 60 with $500k: the withdrawal-rate math, the Social Security bridge, and the gap years before benefits.

26 min
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What Is the Best 401(k) Contribution Percentage?

This walkthrough finds the best 401(k) contribution percentage for your paycheck: the full-match floor, the 10 to 15 percent benchmark, and how it compounds.

29 min
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How Much to Save in 529 Plans: Monthly Targets by Age

How much to save in a 529 plan depends on your goal, runway, and head start. This walkthrough turns college costs into illustrative monthly targets by age.

26 min
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How Much Should You Have Saved by 30? Benchmarks by Age

This walkthrough answers how much should you have saved by 30 with commonly cited salary multiples, honest milestones from 25 to 40, and a catch-up plan.

29 min
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How Much Should You Contribute to Your 401(k)?

This walkthrough turns 401(k) contributions into numbers: the at-least-the-match rule, the 10 to 15 percent benchmark, the tax break, and how time compounds.

26 min
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How Much to Save Each Month to Hit Your Goal: The Math

This walkthrough shows the monthly savings math behind any goal: the simple divide, the with-growth formula, and illustrative amounts for 10k to 100k.

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

How much do I need to retire at 55? A walkthrough of the target multiple, the answer matrix pairing spending with years left, and the coverage decade to 65.

51 min
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How Much Should Be in an Emergency Fund? 3 to 6 Months

This walkthrough answers how much should be in an emergency fund: the essential-expenses floor, the personal multiplier, and where the cash should live.

26 min
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Extra Mortgage Payment: What Paying Extra on Mortgage Saves

Extra mortgage payment math: paying extra on mortgage cuts years off your loan and avoids five figures of interest. See $100 a month, biweekly, and lump sums.

30 min
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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.

33 min