Osvian
Osvian
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Every calculator, grouped by category. Filter to find the one you need — free, no signup.

Money

Free, fast calculators for debt payoff, saving and investing, mortgages, and everyday budgeting. Every tool puts the form first — calculate now, read later.

Compound Interest Calculator

Project savings growth with contributions and interest.

finance

50/30/20 Budget Calculator

Split take-home income into needs, wants, and savings targets.

finance

Credit Card Payoff Calculator

Estimate payoff time, interest, and monthly credit card payoff schedules.

finance

Debt Payoff Planner

Compare snowball and avalanche debt payoff schedules.

finance

Savings Goal Calculator

Solve monthly savings, time, or rate needed to reach a target.

finance

Emergency Fund Calculator

Estimate an emergency fund target from essentials and risk profile.

finance

Loan Amortization Calculator

Build a printable loan amortization schedule with extra payments.

finance

Mortgage Payoff Calculator

Compare your current mortgage schedule with extra payments, lump sums, or biweekly acceleration.

finance

Debt-to-Income Ratio Calculator

Calculate front-end and back-end debt-to-income ratios and compare them with lender guidelines.

finance

Net Worth Calculator

Calculate net worth as assets minus liabilities, with optional local snapshots and no account.

finance

Mortgage Affordability Calculator

Estimate the max home price your income, debts, down payment, DTI target, and housing-cost assumptions can support.

finance

Inflation & Purchasing Power Calculator

Compare historical purchasing power using a BLS CPI-U snapshot, see annualized inflation, and project future dollars.

finance

Retirement / FIRE Calculator

Estimate your FIRE number, Coast FIRE target, and Lean, Fat, or Barista FIRE timeline in today's dollars.

finance

Rent vs Buy Breakeven Calculator

Compare renting and buying with mortgage, tax, maintenance, appreciation, and investment-return assumptions to find the breakeven year.

finance

Paycheck Take-Home Pay Calculator

Estimate per-paycheck take-home pay from gross pay, 2026 US federal withholding, FICA, deductions, and manual state/local tax overrides.

finance

Health

Calculators and printable logs for fitness, body composition, cycle and pregnancy planning, and doctor-visit prep. Estimates only — never medical advice. Your data stays on your device.

BMR Calculator

Basal metabolic rate (Mifflin-St Jeor / Katch-McArdle)

health

Calorie Deficit Calculator

Calorie deficit + weekly weight-loss projection (TDEE-derived)

health

Doctor Visit Checklist

Printable visit-prep checklist with starter questions by visit type, a 5-question cap, and optional pulls from your med list and symptom diary.

health

Pain & Symptom Diary

Daily pain/symptom log with NRS scale, location, and printable export

health

Period Calculator

Predict your next 3 period dates and fertile window. Privacy-first: no accounts, no tracking, your dates never leave your device.

health

Pregnancy Weight Gain Calculator

Pregnancy weight gain vs IOM 2009 trimester ranges

health

Waist-to-Height Ratio

Waist-to-height ratio (WHtR) calculator with Ashwell / NICE NG246 four-band classification. Imperial default; metric toggle; borderline annotation.

health

Blood Sugar Log

Glucose log with ADA-based banding by reading type (fasting / post-meal / random), 7-day running average, CSV + print export. Stored on this device only.

health

BMI Calculator

Body Mass Index calculator with WHO adult bands and CDC LMS pediatric percentiles (ages 2-19). Imperial default; one-click metric.

health

Body Fat Percentage Calculator

Estimate body fat percentage via the US Navy method (height, waist, neck — plus hip for women) with ACE category bands.

health

Blood Pressure Log

Printable BP log with AHA stage banding, 7-day running average, CSV + print export, and on-device storage only.

health

Macro Calculator

Protein, carbs, and fat targets from your TDEE. Protein-anchor default with optional preset ratios.

health

Heart Rate Zone Calculator

Compute training heart-rate zones from age (Tanaka 208 − 0.7·age or 220 − age) and optional resting HR (Karvonen reserve method).

health

Pregnancy Due Date Calculator

Estimate your due date from LMP, IVF transfer, or known conception date. No accounts, no tracking, no data leaves your device.

health

Ovulation and Fertile Window Calculator

Estimate ovulation day and fertile window from your last period and cycle length. Privacy-first: no accounts, no tracking, no data leaves your device.

health

Sleep Cycle Calculator

Bedtime / wake-time planner using the 90-minute sleep-cycle convention plus 14-minute fall-asleep buffer.

health

TDEE Calculator

Daily calories to maintain weight via Mifflin-St Jeor + activity multiplier, plus a 6-row cut/bulk target ladder (calorie-floored).

health

Water Intake Calculator

Daily water target by body weight and activity level, with climate adjustment. US ounces or metric milliliters.

health

Medication List + Wallet Card

Printable medication list with dosage, schedule, and prescriber columns, plus a wallet-card view. Stored on this device only — never sent anywhere.

health

Business

Pricing, planning, and billing calculators for any small operator — set rates, quote jobs, plan capacity, and handle invoices. Built for solo operators and small crews, no login.

Service Business Hourly Rate Calculator

Find the hourly rate a small service business must charge to cover income, overhead, payroll burden, and a profit target. Trade presets, no signup.

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Service Business Profit Margin Calculator

Compute margin from cost and price, derive price from markup, or solve the price needed for a target margin. Trade-typical bands, no signup.

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Lawn Care Pricing Calculator

Per-visit, monthly, and seasonal mowing-quote calculator. Operator mode covers labor, travel, materials, overhead, and margin; homeowner mode gives a quick estimate band.

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Job Cost / Service Price Calculator

Multi-row labor and materials editor with overhead methods (fixed, % of labor, % of total), waste, contingency, and a margin-or-markup recommended price.

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Service-Business Break-Even Jobs Calculator

Jobs per month, week, and day to break even, hit a profit goal, and stay within crew capacity. Includes a +10 / +20 / +50% profit-scenario ladder.

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Invoice Late Fee Calculator

Compute a simple-daily-interest late fee on an overdue invoice. US-default 18% APR with a configurable grace period and optional flat fee.

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Pest Control Pricing Calculator

Operator-first pest control pricing with a transparent multiplier ladder and side-by-side one-time / monthly / quarterly comparison. Severity, accessibility, region, and nine pest-type presets.

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Landscaping Estimate Calculator

Multi-material landscaping estimate with mulch / gravel / sod / pavers / topsoil / concrete volume math, labor, contingency, markup or margin pricing, and a printable line-item estimate. No login.

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Quote Generator

Universal quote / estimate generator with line items, discounts, tax, trade presets, and printable PDF. No signup.

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Technician Utilization Calculator

Crew capacity, billable hours, and headroom planning for service-business owners. No login.

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Route Day Planner

Manual weekly route + schedule sheet for solo operators and small crews. Printable, persists on this device, no map APIs, no signup.

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Recurring vs One-Time Pricing Calculator

Compare weekly, biweekly, every-3-week, monthly, bimonthly, and quarterly recurring service pricing against one-time. Annual revenue, profit, and customer LTV side by side. No login.

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Lawn Care Profit & Revenue Goal Planner

Back-solve the jobs/month and revenue ladder a lawn-care or service business has to deliver to hit a profit goal — with seasonality and crew-capacity sanity check. No login.

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Invoice Template Generator

Trade-specific invoice generator with line items, payment terms, optional late-fee preview, and printable PDF. No signup.

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Pesticide Application Worksheet

General organizational worksheet for pesticide applications. NOT a regulatory record — does not meet state or federal recordkeeping requirements.

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