The toolbox
Find the right tool.
A little help for whatever’s next. Browse free tools for work,
everyday tasks, and the numbers in between.
All tools
Small tools. Useful results.
Developer tools
Format, validate and inspect. Small utilities for your next task.
JSON Beautifier
Format, validate and minify JSON.
DNS Checker
Compare records from public resolvers.
IP Subnet Calculator
Find IPv4 and IPv6 networks, address ranges and CIDR sizes.
Password Generator
Generate strong random passwords locally, with your choice of characters.
Bandwidth Calculator
Estimate file transfer time with decimal and binary data units.
Base64 Encode / Decode
Encode or decode text in your browser, without sending it anywhere.
URL Encode / Decode
Encode or decode text in your browser, without sending it anywhere.
Everyday & productivity tools
Write, convert, scan and check. Everyday tasks, in one place.
World Time Converter
Find a time that works across cities.
Cost Per Use
Track what your purchases cost per use.
QR Code Generator
Create QR codes for links, text, Wi-Fi and contact details.
QR Scanner
Read a QR code from an image or your camera.
Lorem Ipsum Generator
Make sample paragraphs, sentences or words for a layout.
Time Card Calculator
Add a week of work hours, breaks and overnight shifts.
BIN Checker
Look up the issuer and network for a six-digit card prefix.
Credit Card Checker
Check a card number’s length and Luhn checksum locally.
Reverse Image Search
Send an image URL to your chosen visual search engine.
Name Checker
Check public usernames and open social profile searches.
Online Notepad
Write, edit and download a plain-text note in your browser.
Small Text Generator
Turn text into small caps, superscript or subscript characters.
Word Counter
Count words, characters, sentences and reading time.
Domain Name Search
Inspect registration records before choosing a domain.
ROT13 Encoder / Decoder
Apply the reversible ROT13 substitution to English letters.
Morse Code Translator
Translate text to Morse code and decode dots and dashes.
BIMI Checker & Generator
Build a BIMI record and inspect its published DNS text.
Image to Text
Extract printed English text from an image on your device.
Runic Translator
Transliterate Latin letters into an Elder Futhark-style alphabet.
Invisible Character
Copy blank Unicode characters and inspect their code points.
Internet Speed Test
Measure download, upload and latency to HacksDomain.
Wi-Fi QR Scanner
Read the network name and password in a Wi-Fi QR code.
Calculators
Explore an estimate, compare scenarios and understand the numbers.
Loan calculators
4 toolsInvestment calculators
5 toolsSavings calculators
5 toolsTax calculators
2 toolsHousing & Building
8 toolsConcrete Calculator
Estimate slab or cylindrical concrete volume and bag quantities.
BTU Calculator
Estimate a room’s cooling capacity in BTU/h, watts and tons.
Square Footage Calculator
Calculate room and shape areas in square feet, metres and yards.
Stair Calculator
Plan equal risers and estimate a straight stair flight’s run.
Roofing Calculator
Estimate pitched roof area and material allowance from the plan.
Tile Calculator
Estimate floor tiles and boxes with a cutting and waste allowance.
Mulch Calculator
Estimate landscaping volume and the amount of material to order.
Gravel Calculator
Estimate landscaping volume and the amount of material to order.
Fitness calculators
5 toolsBMI Calculator
Calculate adult body mass index and understand its screening range.
Calorie Calculator
Estimate daily maintenance energy from resting needs and activity.
Body Fat Calculator
Estimate body-fat percentage from adult circumference measurements.
BMR Calculator
Estimate resting energy expenditure with the Mifflin–St Jeor equation.
Ideal Weight Calculator
Compare legacy height-based weight estimates with the adult BMI range.
Math calculators
21 toolsBasic Math Calculator
Calculate with a keyboard or keypad, with answer and memory controls.
Scientific Calculator
Calculate with a keyboard or keypad, with answer and memory controls.
Fraction Calculator
Add, subtract, multiply and divide fractions or mixed numbers exactly.
Percentage Calculator
Find a percentage, compare values or apply a percentage change.
Random Number Generator
Generate random integers, with optional sampling without duplicates.
Percent Error Calculator
Measure absolute percentage error against a reference value.
Exponent Calculator
Raise a number to a positive, negative or fractional power.
Binary Calculator
Calculate exact integer results and convert between number bases.
Hex Calculator
Calculate exact integer results and convert between number bases.
Half-Life Calculator
Solve a constant exponential-decay model for the missing quantity.
Quadratic Formula Calculator
Solve quadratic and linear equations, including complex roots.
Log Calculator
Find logarithms in any valid positive base, including e and 10.
Ratio Calculator
Simplify a ratio or solve a missing term in a proportion.
Root Calculator
Find square, cube and higher real roots.
Least Common Multiple Calculator
Find the LCM and GCF of a list of whole numbers exactly.
Greatest Common Factor Calculator
Find the LCM and GCF of a list of whole numbers exactly.
Factor Calculator
List positive factors and the prime factorization of an integer.
Rounding Calculator
Round decimals exactly, including negative values and ties.
Matrix Calculator
Add, multiply, transpose, invert or find a matrix determinant.
Scientific Notation Calculator
Convert decimals and E notation without losing large-number digits.
Big Number Calculator
Perform exact arithmetic on large integers and decimal values.
Statistics calculators
9 toolsStandard Deviation Calculator
Calculate sample and population spread, variance and summary statistics.
Number Sequence Calculator
Generate arithmetic, geometric or Fibonacci terms, or check a simple pattern.
Sample Size Calculator
Estimate survey responses needed for a proportion and margin of error.
Probability Calculator
Combine event probabilities or calculate a binomial distribution.
Statistics Calculator
Summarize a dataset, including quartiles, modes, variance and spread.
Mean, Median, Mode, Range Calculator
Summarize a dataset, including quartiles, modes, variance and spread.
Permutation and Combination Calculator
Count ordered and unordered selections using exact integer arithmetic.
Z-score Calculator
Standardize a value and inspect standard-normal tail probabilities.
Confidence Interval Calculator
Estimate a mean or proportion interval with the appropriate model.
Geometry calculators
9 toolsTriangle Calculator
Solve triangles from sides and angles, including both SSA solutions.
Volume Calculator
Calculate volume and total surface area for common geometric solids.
Surface Area Calculator
Calculate volume and total surface area for common geometric solids.
Slope Calculator
Find the slope, rise, run and equation of a line through two points.
Area Calculator
Find the area of rectangles, triangles, circles and other plane shapes.
Distance Calculator
Find 2D or 3D Cartesian distance and the midpoint between two points.
Circle Calculator
Solve a circle from its radius, diameter, circumference or area.
Pythagorean Theorem Calculator
Solve right-triangle sides, acute angles, area and perimeter.
Right Triangle Calculator
Solve right-triangle sides, acute angles, area and perimeter.
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