All Tools
Find the right InstantTools utility by name or category. Every listed tool opens directly—no sign-up required.
Calculators
Free calculators for everyday decisions, from percentages and tips to payments and payoff.
Percentage Calculator
Calculate a percentage of a number, find what percent one number is of another, or measure percentage change.
Open tool →Tip Calculator
Calculate a tip, total bill, and per-person split for restaurants and services.
Open tool →Discount Calculator
Find sale price, savings, optional sales tax, and final checkout price.
Open tool →Mortgage Payment Calculator
Estimate monthly principal, interest, tax, insurance, and HOA dues.
Open tool →Converters
Fast conversions across common units.
Cups to Grams Converter
Convert cups to grams using an ingredient-specific weight per cup.
Open tool →Pounds to Kilograms Converter
Convert pounds to kilograms with the exact international avoirdupois conversion factor.
Open tool →Fahrenheit to Celsius Converter
Convert a Fahrenheit temperature to Celsius instantly.
Open tool →Inches to Centimeters Converter
Convert inches to centimeters using the exact metric definition.
Open tool →Miles to Kilometers Converter
Convert miles to kilometers for travel, running, and distance measurements.
Open tool →Conversion Hub
Convert measurements, temperatures, data sizes, and more from one place.
Open tool →Time & Date
Plan across time zones and deadlines.
Date Difference Calculator
Find the exact number of days and full weeks between two calendar dates.
Open tool →Age Calculator
Calculate age in completed years, months, and days for any chosen date.
Open tool →Days Until Calculator
Count the calendar days until a future date or since a past date.
Open tool →Workdays Calculator
Count Monday-through-Friday workdays between two dates and optionally exclude holidays.
Open tool →Time Zone Converter
Convert a date and time between major world time zones, including daylight-saving adjustments.
Open tool →Countdown
See exactly how much time remains until a date or event.
Open tool →Money
Payments, payoff, borrowing, and savings growth calculators.
Mortgage Payment Calculator
Estimate a monthly mortgage payment including principal, interest, property tax, insurance, and HOA dues.
Open tool →Mortgage Payoff Calculator
Estimate how long a mortgage will take to repay and how extra monthly payments change the payoff date and interest.
Open tool →Loan Calculator
Calculate the monthly payment, total repayment, and total interest for a fixed-rate installment loan.
Open tool →Auto Loan Calculator
Estimate an auto loan payment using vehicle price, down payment, trade-in value, sales tax, APR, and term.
Open tool →Compound Interest Calculator
Project savings growth from an initial balance, monthly contributions, annual return, and investment period.
Open tool →Text & Developer
Quick utilities for language and technical work.
Word Counter
Count words, characters, sentences, paragraphs, and estimated reading time.
Open tool →Character Counter
Count characters, spaces, words, lines, UTF-8 bytes, and characters remaining against a limit.
Open tool →Case Converter
Convert text to uppercase, lowercase, title, sentence, camel, snake, or kebab case.
Open tool →JSON Formatter & Validator
Validate JSON, format it with readable indentation, and optionally sort object keys.
Open tool →UUID Generator
Generate one or many cryptographically random UUID version 4 identifiers.
Open tool →Meaning Decoder
Decode a word, phrase, abbreviation, or unfamiliar expression.
Open tool →Home
Practical diagnostic guides for common home problems.
Paint Calculator
Estimate wall area, paint volume, and whole gallon cans for a rectangular room.
Open tool →Square Footage Calculator
Calculate area for rectangles, squares, circles, and triangles in square feet.
Open tool →Home Repair
Start with symptom-based guides for plumbing, leaks, water heaters, and more.
Explore guides →Other Utilities
Useful tools that span categories.