Category
Calculators Tools
38 free calculators tools on Toolenza. No signup, no upload by default — browser-only privacy where possible.
All-in-one
Every calculator in tabbed view
Basic Calculator
Free online basic arithmetic calculator
Percentage Calculator
% of a value, what % is X of Y, % change
BMI Calculator
Body Mass Index — metric & imperial
Age Calculator
Exact age + countdown to next birthday
Tip Calculator
Bill split + tip per person
Days Between Dates
Exact days, weeks, months between two dates
Loan Calculator
Monthly payment, total interest, schedule
Discount Calculator
Sale price, % off, savings
Compound Interest
Future value with compounding
GPA Calculator
Weighted GPA from your courses
Salary to Hourly
Convert salary to hourly rate
Developer Calculator
Hex, dec, oct, bin + bitwise ops
Mortgage Calculator
Monthly payment + amortization with PMI / tax / insurance
Refinance Calculator
Should you refinance? Break-even analysis
Auto Loan Calculator
Car payment with sales tax + trade-in
Lease vs Buy
Compare leasing a car to buying it
Investment Calculator
Compound investment with monthly contributions
401(k) / Retirement
Project retirement balance with employer match
ROI Calculator
Return on investment + annualized
Inflation Calculator
How buying power changes over time
Net Worth Tracker
Assets − liabilities, save snapshots
Paycheck Calculator
Take-home pay estimator
Monthly Budget Planner
Plan income, bills & spending — share with family
Zakat Calculator
Annual Zakat on cash, gold, silver & savings (2.5%)
Grade Needed
What's the score I need on the final?
Web Ad Revenue
Estimate display-ad revenue from CPM & traffic
Sleep Calculator
Bedtime / wake-up times around 90-minute cycles
Sales Tax Calculator
Add or extract sales tax (US states + custom)
Significant Figures
Round a number to N significant digits
Scientific Notation
Convert between standard and scientific (a × 10ⁿ)
Logarithm Calculator
log base b of x — any base
Slope Calculator
Slope, midpoint, distance from two points
Pythagorean Theorem
a² + b² = c² — solve any side
Quadratic Equation
Solve ax² + bx + c = 0
Standard Deviation
Mean, variance, std dev from a list
P-Value Calculator
P-value from a z-score (normal)
Confidence Interval
CI for a sample mean (z-based, 80–99%)
Embed these tools on your site
Every tool above has a one-line <iframe> snippet. Drop it into any blog, lesson plan, or knowledge base — your readers get the tool, you get a "Powered by Toolenza" link back.