🏠 Buy the house with eyes open
Clear the debts first (or at least know the plan), see what the down payment grows into if you wait, then run the real monthly payment with PMI and taxes. Three calculators, one honest decision.
Seventeen calculators for the numbers that run your life: percentages, BMI, ages, mortgages, calories, grades, debts, and due dates. The math happens on your device, which matters more for calculators than almost anything else, because look at what people type into them.
The everyday math first (percentages, BMI, ages), then the money decisions, the health numbers, and the life-planning tools. Every calculator uses standard published formulas, works in metric and imperial, and forgets your question the moment you close the tab.
Every percentage question in one place, including tips and discounts.
What is 15% of 80? 12 is what percent of 96? What is the change from 250 to 310? All the phrasings that make percentages slippery, each with its own clearly labeled calculator, plus quick tip and discount tools for restaurant checks and sale racks. The workhorse math tool everyone needs a few times a week and nobody should have to think hard about.
Body Mass Index with a color-coded scale and your healthy weight range.
Height and weight in, BMI out, in metric or imperial, with your category shown on a color-coded scale and the healthy weight range for your height alongside it. Your weight is between you and this page: it is computed on your device and never becomes anyone's data point, which is not the norm for health calculators on the ad-supported web.
Your exact age in years, months, and days, ticking live down to the second.
Forms want your age in years; curiosity wants more. Get the exact figure in years, months, and days, watch the totals tick live in weeks, days, hours, and seconds, count down to the next birthday, and learn which day of the week you were born. Also quietly useful for the paperwork kind of age math: eligibility cutoffs, anniversaries, and how old someone was on a given date.
The real monthly payment: price, rate, term, PMI, and property tax included.
The listing quotes principal and interest; the bank withdraws principal, interest, PMI, and escrowed taxes. This calculator includes the parts that ambush first-time buyers so the number you budget against is the number that actually leaves your account. Run as many scenarios as you like: there is no lender behind this page collecting your finances as leads.
Trig, logs, powers, roots, and factorials, with memory and a live result preview.
The full keypad for when phone calculators fall short: trigonometry with degree and radian modes, logarithms, powers and roots, factorials, the constants that matter, memory functions, and a live preview that shows the result as you build the expression. Works with keyboard input for anyone doing a problem set at speed.
Type a value once, read it in every unit: length, weight, temperature, and more.
The recipe is in grams, the wrench is in inches, the forecast is in Celsius. Enter a value once and see it converted across every unit in the category simultaneously: length, weight, temperature, volume, area, speed, time, and digital storage. No hunting through dropdown pairs; the answer is just on the screen.
Days between dates (including business days), or add time to any date.
How many days until the wedding? What date is 90 days from signing? How many business days does the contract clause actually give you? Count the gap between two dates in years, months, weeks, days, and working days, or add and subtract time from any date. The quiet hero of deadlines, notice periods, and countdowns.
Payment, total interest, payoff date, and what extra payments actually save.
Any loan, laid bare: the monthly payment, the total interest over the full term, and an amortization schedule with a balance chart showing how little principal moves in the early years. The persuasive part is the extra-payment analysis: watch fifty extra dollars a month knock months and real money off the loan, then decide with numbers instead of vibes.
What your money becomes over decades, with contributions and raises modeled.
The most motivating chart in personal finance. Set a starting amount, monthly or yearly contributions with optional annual increases, and a compounding frequency from daily to annual, then watch the stacked chart separate what you deposited from what growth added. The year-by-year table quietly makes the case that the early years matter most.
Your maintenance calories from published formulas, plus honest goal targets.
BMR and TDEE from the Mifflin-St Jeor formula, or Katch-McArdle if you know your body fat percentage, with activity levels explained in plain language. Then the useful part: calorie targets for losing or gaining at different paces, flagged when a target dips below safe minimums, plus three macro splits to start from. The formulas are named because you deserve to know where the numbers come from.
Weighted or unweighted GPA, cumulative tracking, and "what do I need on the final?"
The 4.0 scale handled properly, including the weighted bumps for Honors, AP, and IB courses that most quick calculators fumble. Track cumulative GPA across semesters, and when finals loom, use the final-grade tab for the real question: exactly what score gets the grade you want, including the honest answer when the grade is already locked either way.
Your estimated due date, trimester, and milestone timeline. Computed, not tracked.
From your last period and cycle length: the estimated due date, how far along you are, your current trimester, the likely conception date, and a timeline of milestones ahead. This is the one calculator where the privacy promise matters most, and it holds completely: the calculation happens on your device, and no advertising system learns you asked. Nobody should find out from a coupon mailer.
Clock-in/out times to weekly hours and gross pay, the way payroll counts them.
Enter the week's clock-ins and clock-outs and get totals the way payroll computes them: unpaid breaks deducted, overnight shifts handled, hours rounded to your employer's 5, 6, or 15 minutes, overtime past 40 at time-and-a-half. Add your hourly rate for gross pay, and print a timesheet with signature lines. The two-minute check that your paycheck matches your hours.
Snowball vs avalanche, side by side: debt-free date and total interest for each.
List the debts (balances, rates, minimums) and a monthly budget, and compare the two famous strategies honestly: snowball for momentum, avalanche for math, each with its debt-free date and total interest, against the sobering baseline of minimum payments only. If the minimums cannot outrun the interest, it says so plainly, because that is the finding that changes behavior.
Blood sugar, HbA1c, cholesterol, and more, converted between lab-report units.
The lab report says mmol/L; every article you find says mg/dL. Convert blood sugar, HbA1c (including estimated average glucose), cholesterol, weight, height, and temperature between the units your doctor, your devices, and the internet insist on mixing. Small tool, real relief for anyone managing a condition across unit systems.
One total budget becomes a category-by-category plan you can actually book against.
Enter the total and get it split across venue, catering, photography, and the rest using planner-recommended percentages, then adjust every line to match your priorities and watch the rest rebalance. Booked-versus-planned tracking shows where reality is drifting from the plan, and cost per guest keeps the guest list debate grounded in numbers.
The hourly rate that actually funds your life, not just your salary math.
Dividing a salary by 2,080 hours prices in zero vacation, zero overhead, and zero benefits, which is why so many freelancers quietly earn less than they did employed. This calculator does the honest version: real billable hours, weeks actually worked, expenses, and self-funded benefits, with a sensitivity table showing how the rate moves and a salary-equivalent check for your current rate.
Big decisions rarely need one calculator. These are the sequences people actually run.
Clear the debts first (or at least know the plan), see what the down payment grows into if you wait, then run the real monthly payment with PMI and taxes. Three calculators, one honest decision.
Where you are, what maintenance looks like, and what the lab report actually says. Three tools that turn a vague resolution into numbers, all without your weight becoming anyone's data.
Add up the week the way payroll does, check the paycheck percentage math on that raise, and if you are eyeing independence, see what your rate would really need to be.
The due date and the milestones ahead, the countdown to the day, and every "how many days until" question in between. Life's calendar math, handled privately.