glunty 29 tools in this category. Each runs in your browser.
Calculators trade complex inputs for a clear answer. Cron expressions become English sentences. Time zones convert across multiple targets at once. Wedding cake tier sizes match guest counts using the standard Wilton serving chart. Freelance hourly rates back out from a target salary plus billable-hour reality. Gas costs multiply distance by consumption by price. Pizza counts adjust for adult-vs-kid mix and hunger level. Image dimensions translate between pixels, inches, centimeters, and DPI. Sleep cycle suggestions align with 90-minute REM cycles. Project deadlines skip weekends and US federal holidays.
Each calculator focuses on one clear question and answers it without ceremony. No accounts, no upsells, no advice surrounded by ads. The math runs locally; you can reload the page and keep working without losing context.
Inputs and assumptions are stated plainly so you can decide whether the calculation applies to your situation. The freelancer rate calculator is honest that overhead percentages vary by country; the wedding cake calculator notes that wedding-style cuts give more servings per tier than party-style. Where the math has limits (sleep cycles are an average, federal holidays do not include state holidays), the tool says so plainly.
These are estimates and aids, not professional advice. For load-bearing decisions (financial, medical, legal, contractual), confirm the math against authoritative sources or talk to someone whose job is to know.
The ideas behind these tools, in plain English.
A cron expression is five fields for minute, hour, day of month, month, and day of week that together define when a job runs.
Reading the fields correctly is the difference between a task that runs every minute and one that runs once a year.
A time zone maps a region to an offset from UTC that can shift with daylight saving time, while UTC itself never changes.
Storing and computing in UTC and converting only for display prevents the scheduling and logging bugs that offsets and DST create.
Business-day math counts only working days, skipping weekends and holidays, rather than every calendar day between two dates.
Contracts, shipping, and payroll deadlines depend on it, so a plain day count gives wrong due dates.
Compounding applies growth to a balance that already includes previously earned interest, so the base grows each period.
It explains why more frequent compounding yields more than simple interest and why long horizons matter so much for savings and debt.
Plan free daily credits for Suno, Kling, Leonardo, and Runway before you run out.
Five-field cron, ranges, lists, named days.
Build a cron expression field by field, with live English.
Multi-target time conversion.
Tiers and sizes for any guest count.
Salary target to hourly rate (estimate).
Distance + MPG + price arithmetic.
Adjusts for size, hunger, adult/kid mix.
Pixels and physical at any DPI.
Suggested bedtimes for full 90-min cycles.
Working days + US federal holidays.
Percent of a number, part-of-whole, and percent change.
Tip amount, total, and per-person split for any bill.
Sale price and savings from a percent off; stack discounts, add tax.
Body mass index from kg/cm or pounds and feet/inches, with category.
Estimate a child adult height from both parents heights (mid-parental method).
Exact age in years, months, days, plus total days and next birthday.
Days, weeks, hours, business days, and a full breakdown.
Live countdown to any date; name it, share it by link, or embed it.
Monthly payment, total interest, and cost from amount, APR, and term.
Add tax to a price, or reverse it out of a tax-inclusive total.
Grow a principal with interest and optional monthly contributions.
Hours, minutes, and decimal time between two times.
Simplify a resolution to a ratio, or solve a missing width or height.
Weighted GPA from letter grades and credit hours on the 4.0 scale.
Mean, median, mode, range, variance, and standard deviation, live.
Convert a fraction to a decimal, or a decimal to its simplest fraction.
Preview the next run times for a 5-field cron expression.
Solve pace, time, or distance from any two; speed and race times.