125 free tools
Tools Directory
Every calculator, converter, and browser utility on the site. Filter by name or category, or jump straight to a category page.
- Image Tools 5
- Text Tools 11
- Developer Tools 13
- SEO Tools 5
- Calculators 15
- Finance 13
- Investment 10
- Unit Converters 11
- Date & Time 4
- Health & Fitness 3
- Education 9
- Land & Property 9
- Creator Tools 17
125 tools
- Date & Time
Add or Subtract Calendar Days
Move an ISO date forward or backward by a signed whole-day count. Month and year boundaries…
- Text Tools
Add Prefix and Suffix to Lines
Wrap every line, including empty lines, in a chosen literal prefix and suffix. Useful for plain-text…
- Finance
Add Sales Tax or VAT
Add a user-specified flat tax rate to a before-tax price. This is generic arithmetic, not a…
- Education
Additional Marks for a Target
Find how many more marks are needed for a target final percentage. Enter the full assessment…
- Health & Fitness
Adult BMI
Calculate body mass index from kilograms and centimetres. This is a basic adult screening number, not…
- Health & Fitness
Adult Resting Energy Estimate
Estimate resting energy with the Mifflin–St Jeor equation for adults aged 18–100. The sex parameter selects…
- Finance
Affordable Loan Principal
Calculate the maximum modeled principal supported by a fixed monthly payment, rate, and term. This is…
- Investment
Annual Growth of a Lump Sum
Project one investment using an effective annual return. Unlike nominal-rate compounding, the rate here already includes…
- Calculators
Arithmetic Mean
Calculate the mean of a list of observations. Separate values with commas, spaces, semicolons, or newlines;…
- Calculators
Arithmetic Sequence
Find the nth term and sum of a sequence with a constant difference. Enter the first…
- Education
Attendance Percentage
Compute the percentage of scheduled classes attended so far. Both counts must be whole numbers, and…
- Creator Tools
Audience Engagement Rate
Compare a count of engagement actions with the chosen audience denominator, such as followers or reach.…
- Creator Tools
Audio File Size Estimate
Estimate a compressed audio file’s size from average total bitrate and duration. Use the combined bitrate…
- Creator Tools
Average Cost per Click
Calculate the average advertising cost for each reported click. Counts and spend must refer to the…
- Developer Tools
Base64 to UTF-8
Decode canonical standard padded Base64 into Unicode text. ASCII spaces, tabs, and line breaks around the…
- SEO Tools
Basic JSON-LD Structure Checker
Parse supplied JSON-LD and perform explicitly limited local checks: schema.org string context, simple @type names, name/headline…
- SEO Tools
Basic Schema.org JSON-LD Generator
Create JSON-LD data for an Organization, WebSite, or Article using accurate supplied facts. Article uses a…
- Creator Tools
Bitrate from File Size
Infer average total bitrate from a known file size and duration. The result includes every stream…
- Finance
Break-Even Unit Sales
Estimate the minimum whole units that cover fixed costs at a constant unit price and variable…
- Date & Time
Calendar Age
Calculate completed calendar years on an explicit reference date rather than dividing elapsed days by 365.…
- Date & Time
Calendar Day Difference
Find signed elapsed days between two ISO calendar dates. UTC date arithmetic avoids daylight-saving hour shifts.
- Land & Property
Circular Area and Boundary
Find the area and circumference of a circular feature using its radius. Useful for circular beds,…
- Education
Classes Needed for Attendance
Find how many consecutive future classes you must attend to reach a target attendance percentage, accounting…
- Creator Tools
Click-Through Rate
Measure impression-based click-through rate for a campaign or content placement. Enter whole counts with no more…
- Investment
Compound Annual Growth Rate
Annualize growth between a positive starting value and a nonnegative ending value over a positive number…
- Investment
Compound Interest
Project a starting balance compounded a specified number of times each year. This model assumes a…
- Creator Tools
Cost per Thousand Impressions
Normalize campaign spend to the cost of 1000 served impressions. Use spend and impressions covering the…
- Education
Credit-Weighted GPA
Calculate a credit-weighted grade-point average on your institution’s scale. Enter numeric grade points rather than letter…
- Education
Daily Study Time Planner
Spread a reading or revision workload evenly across available days. Estimate minutes per chapter, then enter…
- Finance
Debt-to-Income Ratio
Compare recurring debt payments with gross income from the same period. Include the debts required by…
- Unit Converters
Digital Storage Converter
Convert bits, bytes, decimal storage units, and binary IEC units without conflating MB with MiB. Enter…
- Finance
Discount and Savings
Calculate the sale price and amount saved from a single discount of 0–100%. Apply further discounts…
- Unit Converters
Duration Unit Converter
Convert elapsed durations using fixed-length seconds, minutes, hours, days, and weeks. This is not a calendar…
- Unit Converters
Energy Converter
Convert energy between joules, kilojoules, kilowatt-hours, thermochemical calories, food kilocalories, and international-table BTUs. Enter a nonnegative…
- Finance
Equal Bill Split
Divide a bill equally among a whole number of people, adding a percentage tip on the…
- SEO Tools
Escaped SEO Meta Tag Generator
Generate a title, description, canonical link, and basic Open Graph title, description, and URL from supplied…
- Land & Property
Excavation and Fill Volume
Estimate the geometric volume of a rectangular excavation or fill layer using consistent linear units.
- Finance
Extract Included Tax
Separate a tax-inclusive total into its before-tax amount and included flat-rate tax. Use the rate originally…
- Calculators
Factorial Calculator
Multiply the positive integers through n for small combinatorics calculations. The supported range preserves exact integer…
- Finance
Fixed-Rate Loan Payment
Calculate equal monthly payments and total interest for a fully amortizing fixed-rate loan. Fees and irregular…
- Developer Tools
Flat JSON to CSV
Convert a nonempty array of up to 10,000 flat objects into quoted CSV with the union…
- Calculators
Fraction Arithmetic
Add, subtract, multiply, or divide two fractions and receive an exact reduced fraction plus its decimal…
- Unit Converters
Fuel Economy Converter
Compare fuel efficiency or consumption with explicit US and imperial gallon definitions. Enter a strictly positive…
- Calculators
Geometric Sequence
Find the nth term and finite sum when every term is multiplied by the same ratio.…
- Creator Tools
HEX to RGB and HSL
Convert an opaque six-digit sRGB hex color into RGB channel values and HSL coordinates. HSL output…
- Developer Tools
HTML Entity Text Decoder
Decode one pass of amp, lt, gt, quot, apos, and valid decimal/hex numeric references. This deliberately…
- Developer Tools
HTML Text Escaper
Escape five sensitive characters in a string for an HTML text or quoted-attribute example. The output…
- Creator Tools
Image Aspect Ratio
Reduce whole-pixel dimensions to their exact width-to-height ratio. Useful for matching artwork to a layout or…
- Investment
Inflation-Adjusted Purchasing Power
Translate a future currency amount into today’s purchasing power using an assumed constant annual inflation rate.
- Education
Institution CGPA Conversion
Convert a percentage using your institution’s published percentage-per-CGPA divisor. The default 9.5 is an example, not…
- Developer Tools
JSON Pretty Printer
Parse genuine JSON and serialize it with a chosen indentation of 1–8 spaces. JSON is parsed,…
- Developer Tools
JSON Syntax Validator
Check whether supplied text parses as bounded-depth JSON and report its top-level type. JSON is parsed,…
- Developer Tools
JSON Whitespace Compactor
Remove unnecessary JSON formatting by parsing and serializing actual JSON. This is not a JavaScript, HTML,…
- Land & Property
Land Area Converter
Convert survey area between acres, hectares, square units, cents, and gunthas using explicit fixed definitions. Regional…
- Unit Converters
Length Converter
Convert physical distances between metric, international foot/yard, and statute-mile units. Enter a nonnegative value and select…
- Calculators
Linear Equation Solver
Solve a single equation ax + b = c. Enter coefficients exactly as they appear, with…
- Text Tools
Literal Find and Replace
Replace every exact, case-sensitive occurrence of a literal string. Regex syntax and replacement tokens have no…
- Creator Tools
Local HTML Invoice Generator
Create an escaped standalone invoice HTML download from seller/buyer text and 1–100 line items. Supply item…
- Image Tools
Local Image Re-encoder and Compressor
Re-encode at original dimensions with a JPEG/WebP quality setting, or use lossless PNG. Lower quality often…
- Image Tools
Local Image Resizer
Fit a PNG or JPEG into a maximum width and height while retaining aspect ratio and…
- Image Tools
Local Pixel Rectangle Cropper
Crop a precise integer rectangle from the browser-decoded, orientation-adjusted source. Coordinates start at the upper-left corner,…
- Image Tools
Local PNG / JPEG / WebP Converter
Convert supported PNG/JPEG input to PNG, JPEG, or browser-supported WebP at unchanged dimensions. Download a file…
- Health & Fitness
Maintenance Energy Estimate
Multiply an adult resting-energy estimate by a selected activity factor to estimate maintenance expenditure. This does…
- Education
Marks to Percentage
Convert earned marks into a percentage of available marks. Supports decimal marks and rejects scores above…
- Finance
Markup to Selling Price
Set a selling price from positive unit cost and a markup percentage. Also see the equivalent…
- Unit Converters
Mass Converter
Convert mass between metric units and international avoirdupois pounds and ounces. This does not calculate force…
- Investment
Monthly Investment Plan
Estimate the future value of equal monthly contributions. Choose whether each contribution is invested at the…
- Investment
Monthly Savings for a Goal
Work backward from a savings target to the equal month-end contribution needed, accounting for an existing…
- Investment
Net Investment ROI
Measure total return after sale proceeds, income distributions, and fees. Use the same currency for every…
- Calculators
Nth Root Calculator
Find square, cube, or higher whole-degree roots. Negative radicands are supported for odd degrees only.
- Calculators
Percentage Calculator
Find a chosen percentage of any numeric amount, including signed changes. Enter the amount and percentage…
- Calculators
Percentage Change
Compare an original and new value to measure relative growth or decline. A zero original value…
- Land & Property
Plot Purchase Cost
Estimate a land purchase from area and price per matching area unit, then add a single…
- Calculators
Power Calculator
Raise a real base to an exponent. Negative bases require whole-number exponents so the result stays…
- Unit Converters
Pressure Converter
Convert pressure magnitudes between pascals, kilopascals, bar, standard atmospheres, and pounds per square inch. Enter a…
- Finance
Profit Margin
Find gross or net margin from revenue and the costs you choose to include. Keep revenue…
- Creator Tools
Proportional Resize Dimensions
Calculate the height needed to preserve an image or video’s proportions at a new target width.…
- Calculators
Quadratic Real Roots
Solve ax² + bx + c = 0 with a nonzero leading coefficient. Receive both real…
- Creator Tools
Random UUID v4 Generator
Generate 1–100 RFC 9562 version 4 UUIDs using cryptographic random bytes. Version and variant bits are…
- Text Tools
Reading Time Estimate
Estimate a reading duration from your own reading speed. Paste the complete passage and enter a…
- Land & Property
Rectangular Fencing Cost
Estimate boundary fencing material or all-in installation cost for a rectangle, deducting total gate openings from…
- Land & Property
Rectangular Plot Area
Measure the area of a rectangular plot, floor, or garden using perpendicular length and width in…
- Finance
Remaining Loan Balance
Find the outstanding balance immediately after a specified number of scheduled monthly payments. Assumes a fixed…
- Text Tools
Remove Duplicate Lines
Remove repeated lines while keeping the order of first occurrence. Comparisons are exact and case-sensitive; spaces…
- Education
Required Final Exam Grade
Determine the final-exam percentage needed for a target overall grade. Your current percentage must describe only…
- Creator Tools
Return on Ad Spend
Compare attributed campaign revenue with advertising spend as a revenue multiple. Attribution assumptions come from your…
- Creator Tools
Revenue per Thousand Views
Normalize recognized creator revenue to 1000 views. Choose a consistent view definition and reporting period for…
- Calculators
Reverse Percentage
Recover the original amount before a known percentage increase or decrease. Use a negative percentage for…
- Text Tools
Reverse Unicode Text
Reverse a string by Unicode code points rather than UTF-16 halves. Useful for simple text experiments;…
- SEO Tools
Robots.txt Generator
Generate one crawler group with allow or disallow paths and an optional sitemap. Use * or…
- Investment
Rule of 72 Doubling Time
Get a quick approximate doubling period from a positive annual percentage return. Best used for rough…
- Finance
Salary to Hourly Equivalent
Translate annual gross salary into an hourly equivalent using your paid working weeks and hours per…
- Investment
Savings Withdrawal Duration
Estimate how long a balance supports fixed monthly withdrawals with constant modeled growth. Withdrawals are made…
- Creator Tools
Secure Random Integer
Draw one uniformly distributed whole number between inclusive bounds. Both bounds must fit signed 32-bit integers,…
- Creator Tools
Secure Random Password Generator
Generate 1–20 passwords, each 8–128 characters, using Web Crypto and unbiased sampling. Select all symbols, alphanumeric…
- Developer Tools
SHA-256 Text Digest
Compute the SHA-256 digest of exact Unicode text encoded as UTF-8. The engine returns a Promise…
- Investment
Simple Interest
Calculate interest charged only on the original principal, without interest-on-interest. Enter the annual rate and duration…
- Calculators
Simplify a Ratio
Reduce a pair of positive whole numbers to their smallest equivalent ratio using their greatest common…
- Text Tools
Sort Lines Lexically
Sort one entry per line in ascending or descending JavaScript lexical order. Duplicates and empty lines…
- Unit Converters
Speed Converter
Translate nonnegative speeds among metres per second, kilometres per hour, miles per hour, and nautical knots.…
- Unit Converters
Square Area Converter
Convert measured surface areas from tiny square millimetres to square kilometres and square miles. For acres…
- Image Tools
Square PNG Favicon Generator
Center-crop a supported image to a square and resize it to 16–512 pixels for a PNG…
- Unit Converters
Temperature Converter
Convert absolute temperatures among Celsius, Fahrenheit, and kelvin. Negative Celsius and Fahrenheit inputs are valid above…
- Text Tools
Text Case Converter
Convert text to uppercase, lowercase, simple title case, or simple sentence case using Unicode default case…
- Developer Tools
Text to UTF-8 Binary
Represent Unicode text as space-separated eight-bit UTF-8 bytes. A single visible character may need several byte…
- Land & Property
Three-Side Triangle Area
Calculate triangle area from three measured boundary lengths. Strict triangle inequalities prevent impossible or flat plots…
- Finance
Tip Calculator
Calculate a gratuity and the resulting total bill from the amount you choose to tip on.…
- Land & Property
Trapezoid Plot Area
Estimate area where two plot boundaries are parallel. Enter the two parallel lengths and their perpendicular…
- Land & Property
Triangle Base–Height Area
Calculate triangular land area from a base and its perpendicular height. The height is not the…
- Text Tools
Unicode Normalizer
Normalize canonically equivalent or compatibility-equivalent Unicode text. Choose NFC/NFD for canonical forms or NFKC/NFKD when compatibility…
- Text Tools
Unicode Slug Generator
Create a readable lowercase slug from a heading. Compatibility decomposition removes combining marks; runs of punctuation…
- Developer Tools
URL Component Decoder
Decode percent-encoded UTF-8 in a URL component. Malformed escapes or invalid UTF-8 return a clear error…
- Developer Tools
URL Component Encoder
Percent-encode one query value or path component using UTF-8. Do not paste an entire URL unless…
- Developer Tools
UTF-8 Binary to Text
Decode whitespace-separated groups of exactly eight binary digits as UTF-8 text. Invalid groups and malformed UTF-8…
- Developer Tools
UTF-8 to Base64
Encode Unicode text as UTF-8 bytes and then standard padded Base64. Whitespace and line endings in…
- SEO Tools
UTM Campaign URL Builder
Build an HTTP(S) campaign URL without visiting it. Source, medium, and campaign are required; term and…
- Creator Tools
Video File Size Estimate
Estimate encoded video size from average video bitrate, audio bitrate, and duration. This models bitrate, not…
- Creator Tools
Visitor Conversion Rate
Measure the share of unique visitors who converted at least once. Use visitor counts rather than…
- Unit Converters
Volume and Capacity Converter
Convert capacities and geometric volumes with explicit US and imperial gallon definitions. Enter a nonnegative value…
- Date & Time
Weekday Count
Count Monday-through-Friday dates in a range, including the start and excluding the end. This is a…
- Calculators
Weighted Average
Combine values whose importance differs. Enter matching value and weight lists in the same order, with…
- Education
Weighted Course Grade
Combine assignment or exam percentages using their course weights. Enter matching score and weight lists, with…
- Calculators
What Percent of a Total?
Express a part as a percentage of a positive reference total. The part can exceed the…
- Text Tools
Whitespace Cleaner
Clean pasted spacing without collapsing all paragraphs into one line. Normalize CRLF/CR line endings, reduce horizontal…
- Text Tools
Word and Unicode Character Counter
Paste text to count whitespace-separated words, Unicode code points, UTF-16 units, non-whitespace characters, lines, and UTF-8…
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