HarborPlain

Tools

Every HarborPlain calculator and tracker in one place. All are free, ask for no email, and run entirely in your browser. Search by name or filter to the decision in front of you.

Showing 20 of 20 tools

InsuranceQuick estimate

Life Insurance Calculator

A quick 10-second ballpark from the 10× income rule: a fast starting point, no line-by-line breakdown. Want an exact figure? Use the detailed DIME calculator.

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InsuranceDetailed

Life Insurance Needs Calculator

The detailed DIME worksheet (debts, income, mortgage, and education, minus what you already have) for a precise, obligation-based number, with an illustrative 20-year term premium.

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Insurance

HDHP vs PPO Baby Cost Comparator

Compare the total annual cost of an HDHP (with HSA) and a PPO for a childbirth year: premiums, deductible, coinsurance, and out-of-pocket max. Computes both from your numbers; no assumed winner.

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InsuranceCoverage gap

COBRA Cost Calculator

See your real monthly COBRA cost when job-based coverage ends: the full premium plus the admin fee, the jump from your old paycheck share, and a side-by-side with a Marketplace plan.

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InsuranceLiability

Umbrella Insurance Calculator

How much excess liability coverage to carry: protect your net worth and income on top of your auto and home limits, with an illustrative premium range.

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Insurance

Stay-at-Home Parent Value Calculator

Put a dollar figure on the childcare, cooking, cleaning, driving, and admin a stay-at-home parent does, then see the life cover it would take to replace it.

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InsuranceMaternity leave

Short-Term Disability Calculator

Estimate what short-term disability pays during maternity leave: weekly benefit, paid weeks after the waiting period, and the income gap to plan around. Works from your own plan terms.

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Money

Baby Cost Calculator

Estimate your baby's first-year cost: adjust eight categories, compare feeding and childcare scenarios, and see the monthly figure.

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MoneyNanny vs daycare

Nanny Tax Calculator

The true cost of a nanny: Social Security, Medicare, FUTA, and state unemployment taxes on top of wages, then a nanny vs daycare comparison that flips with the number of children.

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Money

529 vs UTMA Comparator

Project what a 529 plan and an UTMA account would each be worth at 18, and see how they differ on taxes, control, and financial aid.

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MoneyRetirement

Custodial Roth IRA Calculator

See what a working child's custodial Roth IRA could grow to by retirement: small early contributions, capped at earned income, compounding tax-free for decades.

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MoneyBy state

529 State Tax-Deduction Optimizer

Pick your state and see the state income-tax you'd save on a 529 contribution: deduction or credit, per-beneficiary caps, parity, owner-only, and April deadlines. All 50 states + DC.

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MoneyUTMA tax

Kiddie Tax Calculator

Estimate the tax on a child's unearned income: the tax-free tier, the child's rate, and the amount taxed at the parent's rate. The UTMA's main drawback, quantified.

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Money

College Savings Goal Calculator

Set a college-cost target and see the monthly saving required to hit it, with college inflation and growth on what you already have.

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Money

HSA Contribution Limit Calculator

Prorate your HSA limit for a mid-year start: the safe sum-of-months figure and the full-year last-month rule side by side, with the testing-period trap and 55+ catch-up. 2025 & 2026 IRS limits.

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Legal

Will & Guardianship Checklist

Tick through the guardian, will, and beneficiary decisions that protect your child, then print the summary for your attorney.

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Health

Pregnancy Week-by-Week Tracker

See your current week, trimester, and countdown, with a checklist of the money and legal decisions to make before the birth.

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HealthWith budget

Baby Registry Checklist & Budget

Every item worth putting on a baby registry, grouped and marked essential or nice-to-have, with a running budget that adds up as you tick. Saved on your device.

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HealthPacking list

Hospital Bag Checklist

A tickable packing list for the birth: what to bring for you, the baby, and your partner, plus the paperwork. Saved on your device, printable, no medical advice.

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Health

Diaper Size & Cost Calculator

Find the right diaper size by weight (Pampers and Huggies kept separate, since the brands differ), then estimate how many a month and the cost to potty training.

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