Free loan and EMI calculator to estimate monthly repayments, total interest, total repayment, and an amortisation schedule from your loan amount, interest rate, and term.

Invoice Generator

Free invoice generator to create a clear, printable invoice with editable line items, discounts, tax, and currency labels in your browser.

Compound Interest Calculator

See how an investment can grow with regular contributions.

Savings Calculator

Plan regular savings and see the estimated future balance.

GST/VAT Calculator

Add tax to a price or remove it from an inclusive total.

Date Calculator

Free date calculator to add or subtract whole days, months, or years from a starting date and see the resulting calendar date.

Days Between Dates Calculator

Count the exclusive days, weeks, and hours between two dates.

Weight Converter

Convert metric and imperial weight units in every direction.

Volume Converter

Convert kitchen and metric volume units with clear labels.

Speed Converter

Switch between m/s, km/h, mph, ft/s, and knots.

Character Counter

Track characters, spaces, words, lines, and paragraphs.

Mortgage Calculator

Free mortgage calculator to estimate monthly payments for a home purchase or refinance.

Fuel Cost Calculator

Estimate how much fuel a trip will use and what it will cost.

Hours Calculator

Find net working hours from a start time, end time, and break.

Time Duration Calculator

Find the duration between two times, including overnight.

Area Converter

Convert between metric and imperial area units instantly.

Data Storage Converter

Convert between decimal (KB, MB) and binary (KiB, MiB) storage units.

Tip Calculator & Bill Split

Free tip calculator to work out the tip and split a bill across any number of people.

Recipe Scaler

Scale a recipe up or down by changing the number of servings.

Password Strength Checker

Check how strong a password is, entirely in your browser.

Random Number Generator

Free random number generator to generate integers or decimals within any range.

Mortgage Overpayment Calculator

See how extra repayments reduce your interest and shorten your loan term.

Investment Return Calculator

Project the growth of an investment with regular contributions.

Break-Even Calculator

Find how many units you need to sell to cover your costs.

Business Days Calculator

Count weekday-only days between two dates, both inclusive.

Energy Converter

Convert between joules, calories, kilowatt-hours, BTU, and more.

Pressure Converter

Convert between pascals, bar, PSI, atm, torr, and mmHg.

Frequency Converter

Convert between Hz, kHz, MHz, GHz, and RPM.

UUID Generator

Generate cryptographically random UUID v4 values in your browser.

Timestamp Converter

Convert Unix timestamps to readable dates, and vice versa.

Scientific Calculator

Free scientific calculator to evaluate expressions with powers, square roots, and percentages.

Calorie Calculator

Estimate daily calorie needs from your body and activity profile.

Sleep Calculator

Find estimated bedtimes or wake-up times using sleep cycles.

GPA Calculator

Calculate a weighted GPA from grade points and course credits.

Final Grade Calculator

Find the final assessment score needed to reach your target grade.

Percentage Change Calculator

Calculate percentage increase, decrease, and absolute difference.

Profit Margin Calculator

Calculate profit or loss, margin percentage, and markup percentage.

Pace Calculator

Calculate distance, elapsed time, or running pace.

Concrete Calculator

Estimate concrete volume from length, width, and depth.

Countdown Calculator

Count down the days, hours, minutes, and seconds to a future date.

Paint Calculator

Estimate paint litres from surface area, coats, and coverage.

Salary to Hourly Calculator

Turn an annual salary into hourly, weekly, and monthly pay.

Debt Payoff Calculator

Estimate how long a balance will take to repay at a fixed payment.

Mortgage Affordability Calculator

Estimate a home price from income, debts, deposit, rate, and term.

Test Grade Calculator

Convert points earned into a test percentage and letter grade.

Average Calculator

Find the mean, median, minimum, and maximum of a number list.

Fraction Calculator

Add, subtract, multiply, or divide two fractions.

Time Zone Converter

Convert a date and time between common time zones.

Square Footage Calculator

Calculate the area and perimeter of a rectangular room or space.

Freelance Rate Calculator

Free freelance rate calculator to estimate an hourly and daily rate based on your income goal, expenses, working time, and billable hours.

Simple Interest Calculator

Free simple interest calculator to calculate interest and the total amount from principal, rate, and time.

Savings Goal Calculator

Free savings goal calculator to estimate how long regular contributions may take to reach a target.

Overtime Pay Calculator

Estimate regular pay, overtime pay, and total earnings from hourly work.

Rent vs Buy Calculator

Compare estimated monthly rent with a home payment and ownership costs.

APR Calculator

Estimate annual percentage rate from a loan, fees, payment, and term.

Emergency Fund Calculator

Set an emergency-fund target and see how many months your savings cover.

Budget Allocation Calculator

Turn budget percentages into clear monthly amounts.

Markup vs Margin Calculator

Compare markup, selling price, profit, and profit margin from a cost.

Net Worth Calculator

Add assets and liabilities to estimate your current net worth.

Commission Calculator

Calculate commission earnings from sales, a rate, and optional base pay.

Days From Today Calculator

Find how many calendar days a date is from today.

Week Number Calculator

Find the ISO week number and week-year for any calendar date.

Day of the Week Calculator

Find which weekday matches any date.

Workday Calculator

Add or subtract weekdays from a starting date.

Work Time Card Calculator

Calculate net shift time after subtracting an unpaid break.

Date Difference with Time Calculator

Calculate the elapsed time between two dates and clock times.

Number Base Converter

Convert whole numbers between decimal, binary, octal, and hexadecimal.

Roman Numeral Converter

Convert standard Roman numerals to numbers and back.

Colour Converter

Convert six-digit hexadecimal colours to RGB channels and back.

Area Calculator

Free area calculator to calculate the area of a rectangle, circle, or triangle from dimensions.

Volume Calculator

Free volume calculator to calculate the volume of a box, cylinder, or sphere.

Decimal to Fraction Calculator

Turn a finite decimal into a reduced fraction.

Ratio Calculator

Simplify a ratio and compare its two values.

Standard Deviation Calculator

Calculate the mean, variance, and population or sample standard deviation.

Prime Number Checker

Check whether a whole number is prime.

Scientific Notation Converter

Express a number as a coefficient multiplied by a power of ten.

Right Triangle Solver

Solve a right triangle from any two positive side lengths.

Prime Factorization Calculator

Break a whole number into its prime factors.

GCD & LCM Calculator

Find the greatest common divisor and least common multiple of two integers.

Permutations & Combinations Calculator

Calculate ordered permutations and unordered combinations.

Tile Calculator

Estimate tile quantities for an area with an optional waste allowance.

Mulch Calculator

Estimate mulch volume in cubic yards and two-cubic-foot bags.

Gravel Calculator

Estimate gravel volume and approximate weight from area and depth.

Stair Calculator

Estimate riser count, actual riser height, and tread count.

Unit Price Calculator

Find the price per item, weight, volume, or other quantity.

Aspect Ratio Calculator

Reduce image or screen dimensions to a simplified aspect ratio.

Data Transfer Time Calculator

Estimate how long a file takes to transfer at a stated connection speed.

Image File Size Estimator

Estimate uncompressed image size from dimensions, channels, and bit depth.

CSV to JSON Converter

Turn a simple comma-separated table into formatted JSON.

URL Parser

Break a complete URL into protocol, host, path, query, and hash.

Base64 Encoder/Decoder

Free Base64 encoder/decoder to encode text or decode a Base64 value locally.

URL Encoder/Decoder

Free URL encoder/decoder to encode or decode text for safe use inside a URL component.

JSON Formatter & Validator

Validate JSON and format it with readable indentation.

HTML Formatter

Add readable line breaks to compact HTML markup.

Regex Tester

Test a regular expression against sample text in your browser.

Lorem Ipsum Generator

Generate a few paragraphs of neutral placeholder copy.

Text Sorter & Deduplicator

Sort lines alphabetically and remove repeated entries.

Text Diff Checker

Compare two texts line by line and show additions and removals.

Slug Generator

Turn a title or phrase into a clean lowercase URL slug.

HTML Entity Encoder/Decoder

Escape or unescape common HTML entities such as ampersands and angle brackets.

Number to Words Converter

Write a whole number in clear English words.

Weighted Average Calculator

Calculate an average where each value carries a different weight.

Percent Error Calculator

Compare a measured value with an accepted reference.

Statistical Summary Calculator

Find mean, median, mode, and range for a list of numbers.

Quadratic Equation Solver

Solve ax² + bx + c = 0 and identify its roots.

Probability Calculator

Express equally likely outcomes as a fraction, decimal, and percent.

Heart Rate Zone Calculator

Estimate broad exercise heart-rate zones from a maximum rate.

One Rep Max Calculator

Estimate one-repetition maximum from a submaximal lift.

Electricity Cost Calculator

Estimate appliance electricity use and cost from watts, time, and tariff.

Debt-to-Income Calculator

Compare monthly debt payments with gross monthly income.

Meeting Cost Calculator

Estimate the staff time cost of a recurring meeting.

Freelancer Hourly Rate Calculator

Plan a freelance hourly rate from income, costs, and billable time.

Cash Runway Calculator

Estimate how many months available cash can cover net monthly burn.

Profit and Loss Calculator

Summarise revenue, costs, expenses, profit, and margins.

Recurring Payment Cost Calculator

Compare recurring payments as monthly and annual total costs.

Rent Affordability Calculator

Compare rent with a personal income-ratio target.

Meeting Time Overlap Planner

Find the overlap between two manually entered work windows.

Pomodoro Timer

Run alternating focus and break cycles in your browser.

Date Recurrence Planner

Generate a bounded list of recurring calendar dates.

Monthly Calendar Generator

Create a simple month calendar ready to print or download.

Fuel Economy Converter

Convert US MPG, Imperial MPG, and litres per 100 kilometres.

Angle Converter

Convert degrees, radians, and gradians.

Data Rate Converter

Convert network transfer rates between bits and bytes per second.

Time Unit Converter

Convert fixed durations from seconds to weeks.

Readability Checker

Estimate English reading ease for a short passage.

Markdown Preview Formatter

Preview a small safe subset of Markdown locally.

Whitespace Cleaner

Trim, collapse, or normalise whitespace in pasted text.

Markdown Table Generator

Turn simple comma, tab, or pipe-separated rows into a Markdown table.

Colour Palette Generator

Generate coordinated hex colour suggestions from a seed colour.

Random Picker

Choose one item from a simple one-per-line list.

Image to WebP Converter

Free image to WebP converter to convert JPG, PNG, GIF, BMP, and other supported images in your browser. Adjust quality, compare file sizes, and download your WebP image privately.

Colour Codes

Free colour codes tool to pick, explore, compare, and copy colour codes for websites, apps, and digital designs.

Colour Contrast Checker

Check the contrast ratio of two solid hex colours.

Screen Resolution & PPI Calculator

Estimate a display’s pixel density from resolution and diagonal size.

File Checksum Generator

Calculate a SHA-256 checksum for a selected local file.

JSON to CSV Converter

Convert a flat JSON record list to CSV and download it.

Image Resize & Compress

Resize and compress a selected local image before downloading it.

PX to REM Converter

Convert CSS pixels to rem using your chosen root font size.

Data URI Generator

Encode locally entered text as a complete data URI.

JWT Decoder

Decode a JWT header and payload locally without verification.

File Metadata Inspector

Inspect browser-visible properties of a selected local file.

Colour Blindness Simulator

Preview an illustrative colour-vision simulation for one hex colour.

URL Query Builder

Add encoded query parameters to a complete URL.

Image Format Converter

Convert a selected local image to a browser-supported format.

Shared Expense Splitter

Split group bills and purchases by payer and participant.

Cost Split by Percentage Calculator

Divide a shared cost using custom percentages.

Subscription Plan Comparison

Compare up to three subscription plans using your own costs and billing cycles.

Job Offer Comparison Calculator

Compare two job offers using pay, hours, commute, and benefit assumptions.

Recipe Cost Calculator

Estimate ingredient and per-serving recipe cost from package prices.

Price Per Use Calculator

Estimate an item’s cost for each expected use.

Timesheet Calculator

Total multiple daily shifts, breaks, and overnight work hours.

Billable Hours and Project Cost Calculator

Estimate a project total from billable hours, rates, and direct costs.

Project Time Estimate Calculator

Estimate a project range from task quantities, durations, and a buffer.

Trip Cost Calculator

Estimate travel expenses per day and per person.

EV Charging Cost Calculator

Estimate EV charging cost from energy, tariff, and charging loss.

Parking Cost Calculator

Estimate parking charges from block rates and daily caps.

Commute Cost Comparison

Compare driving, EV, and public-transport commute costs.

Appliance Running Cost Comparison

Compare electricity costs for up to three appliances.

Average Speed Calculator

Calculate average speed, distance, or time from the other two.

TV Size & Viewing Distance Calculator

Calculate TV screen dimensions from diagonal and aspect ratio.

Furniture Fit Calculator

Compare furniture dimensions with a room, opening, or doorway.

Image Print Size Calculator

Convert image pixels and PPI into estimated print dimensions.

Filename Cleaner

Preview cleaner filenames from a pasted list.

File Size Comparison

Compare local file sizes with clear decimal or binary units.

Study Session Planner

Plan subjects, study durations, breaks, and an optional start time.

Flashcard Randomizer

Shuffle self-authored flashcards locally into a new study order.

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