Helpful Guides
Short articles that answer a task, then point to the tool that does it.
Guide
How to Calculate Percentage
How to calculate a percentage: X% of a number, a number as a percent of another, and percent increase or decrease.
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How to Compress an Image Without Losing Quality
Resize a photo first, pick JPEG, WebP, or PNG, then compress in small steps while you compare a preview. The file stays in your browser.
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What Is JSON?
JSON is a text format for objects and arrays. See how to read it, why it fails to parse, and how to format it in the browser.
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How to Create a UTM URL
Add utm_source, utm_medium, and utm_campaign to a destination URL so analytics can tell campaigns apart.
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How to Calculate Age
Count age in years, months, and days from a date of birth using the civil calendar, including leap days.
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How to Work with PDFs in Your Browser
Compress a PDF, extract text, check metadata, or merge pages in the browser without uploading the file.
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How to Clean and Compare Text
Remove duplicate lines, tidy whitespace, sort a list, and compare two drafts locally in the browser.
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How to Calculate a Tip
Multiply the bill by the tip rate, add it to the total, and divide by the number of people when the check is shared equally.
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How to Convert a Hex Color to RGB
Split a hex color into red, green, and blue pairs and convert each pair from base 16 to a number from 0 to 255.
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How to Count the Pages in a PDF
Read the number of pages stored in a PDF, including blank pages and a cover, before you split or merge the file.
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How to Add Sales Tax to a Price
Multiply a pre-tax price by the tax rate you type, round the tax to cents, and add it to the price.
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How to Convert Length, Weight, and Temperature
Convert length and weight by a fixed factor, and temperature with the Celsius, Fahrenheit, and Kelvin formulas.
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How to Count the Days Between Two Dates
Count midnights between two dates, then read weeks and a calendar span in years, months, and days.
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How to Count Characters in a Text
Count Unicode characters, including spaces, plus a total without spaces, words, and lines.
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How to Pick a Color and Copy HEX, RGB, or HSL
Choose one opaque color with the browser color control and copy it as HEX, RGB, or HSL.
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How to List the Dominant Colors in an Image
Sample a JPG, PNG, or WebP and list 3 to 10 colors with each color's share of the sampled pixels.
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How to Read a QR Code from the Camera or an Image
Decode one QR code from the camera or from a PNG or JPG, then open a link only after you read it.
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How to Generate a Random Number
Draw 1 to 200 integers or decimals between a minimum and a maximum. Unique mode works for integers only.
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How to Estimate a Fuel Cost
Divide distance by fuel economy, then multiply by the price and the number of trips.
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How to Calculate an Aspect Ratio
Divide width and height by their greatest common divisor, or find the missing side from a ratio.
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How to Percent-Encode a URL Value
Encode a URL component with encodeURIComponent, or decode a percent-encoded string back to text.
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How to Read a Unix Timestamp
Turn seconds or milliseconds since 1970-01-01 UTC into a UTC date, or turn a UTC date back into a timestamp.
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How to Escape HTML So It Shows as Text
Replace <, >, &, and quotes with entities so markup is shown as text, or turn those entities back into characters.
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How to Check Contrast Between Two Colors
Compare two solid colors and read the WCAG 2 ratio, including AA and AAA for normal and large text.
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How to Write a CSS Gradient
Build a linear, radial or conic CSS gradient from at least two color stops and copy the background or gradient text CSS.
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How to Write One CSS Box Shadow
Set one offset, blur, spread, color, and opacity, then copy a single box-shadow declaration.
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How to Turn a JSON Array into CSV
Turn a JSON array of objects into CSV. The first row is the keys, and commas inside cells are quoted.
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How to Turn CSV into JSON
Use the first CSV row as keys and turn each following row into a JSON object.
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How to Test a Regular Expression
Run a JavaScript regular expression on sample text and read each match, its index, and its capture groups.
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How to Hash Text with SHA-256, SHA-384, or SHA-512
Hash pasted text with SHA-256, SHA-384, or SHA-512. The hex is a fingerprint, not a way back to the text.
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How to Generate Lorem Ipsum
Generate 1 to 20 placeholder paragraphs, 1 to 50 sentences, or 1 to 500 words of lorem ipsum.
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How to Find and Replace Text
Replace the first exact match or every match. Case can be ignored. This is not a regular expression.
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How to Remove Line Breaks
Turn line breaks into spaces, delete them, or keep a blank line between paragraphs.
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How to Add Line Numbers
Put a starting number and a separator in front of each line without changing the line text.
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How to Turn a Number into Words
Write a whole number from zero through 999,999,999 in English words, or parse a simple phrase back to digits.
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How to Convert Text to Morse Code
Convert A to Z and 0 to 9 into Morse dots and dashes, or turn that code back into text.
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How to Convert Numbers and Roman Numerals
Convert 1 to 3999 into standard Roman numerals, or a valid numeral back into a number.
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How to Generate a Password in the Browser
Generate a password from 8 to 64 characters in the browser. The strength label is an estimate from length and set size.
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How to Build a Prompt, and When That Text Leaves the Browser
Generate prompt stays in the browser. Generate with AI sends topic, goal, and the other listed fields to Gemini.
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How to Write a Video Prompt Without Rendering a Clip
Build prompt writes a shot in the browser. Generate with AI sends the shot fields to Gemini and returns text, not a video.
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How to Shorten an Article in the Browser or with Gemini
Shorten article edits the draft in the browser. Compress with AI sends the article and the selected setting to Gemini.
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How to Add or Subtract Hours and Minutes
Add or subtract hours and minutes by converting both sides to minutes, then splitting the signed total back into hours and a remainder.
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How to Read a Cron Expression
Read a five-field cron expression. When both day fields are set, cron matches either day, not both.
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How to Rewrite Stock Phrasing
Rewrite text stays in the browser. Humanize with AI sends the draft. The tool does not try to bypass an AI detector, and it does not claim the result will look like a particular kind of author.
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How to Find the Mean, Median, and Mode
Find the mean, median, and mode of a comma-separated list. 1, 2, 3, 4 has a mean of 2.5 and no mode.
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How to Read Text from a Photo
Read English text from one JPG, PNG, or WebP in the browser. The first run downloads about 6.6 MB, and a clear sign can still come back wrong.
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How to Turn a Word Document into a PDF
Read the words from a .docx file into a plain PDF. Images, table grids, headers, footers, and text styling are left out.
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How to Make a Simple Favicon
Draw PNG icons at 16, 32, and 180 pixels. The ICO file holds the 16 and 32 pixel images only.
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How to Repeat a Word or Line
Repeat text from 1 to 200 times with nothing, a space, or a new line between copies. The separator is not added after the last copy.
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How to Write Meta Tags
Write a charset tag, a title, and a robots tag, plus optional description and social tags. The page does not fetch a live URL.
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How to Check an Open Graph Preview
Check preview sends the URL off this device to fetch the page. The site reads the share tags and does not save the page.
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How to Write a .gitignore File
Build .gitignore text from Node, Next.js, environment, and other templates. Generating the text does not update a repository.
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How to Rate a Password
Rate a password from its length and character pool. Under 50 bits is Short, under 80 is Moderate, and 80 or more is Strong.
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How Compound Interest Grows Your Money
Compound interest adds growth onto a balance over time. See the monthly method this calculator uses, including an optional contribution.
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How a Loan Payment Is Calculated
An installment payment is estimated from the amount, annual rate, and term. A separate fee is not rolled into that payment.
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How a Mortgage Payment Is Estimated
A mortgage estimate starts from home price and down payment, then can add tax, insurance, HOA, and PMI.
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How to Estimate a Car Loan Payment
A car payment estimate starts from vehicle price, then subtracts down payment and trade-in after tax, fees, and add-ons.
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How a Home Price Estimate From Income Works
This estimate sizes a home price from income, debts, and a target ratio. It is not a promise of what you can safely buy.
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How to Compare Renting and Buying Costs
How to compare an estimated rent cost with an estimated buying cost for the same period.
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How to Plan a Debt Payoff
How a payoff timeline is estimated when more than one debt is being paid down.
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How Long a Credit Card Balance Takes to Pay Off
How long one card balance can take to pay off at a chosen payment.
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How Much to Save for a Goal
At 0% interest, divide the gap between the target and what you have saved by the number of deposits.
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How to Turn Hours or a Salary into Pay
How a yearly or weekly salary converts to an hourly rate, including overtime hours.
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What a Paycheck Estimate Includes
What this paycheck estimate includes, and which taxes and deductions it does not calculate.
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How to Calculate a GPA
How a 4.0 GPA is credit-weighted from course grades.
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How to calculate square footage
How to calculate room area in square feet or square meters from length and width.
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How to Count Business Days
How weekdays between two dates are counted, without treating that span as an age.
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What Base64 Is, and How to Encode Text
Encode text to Base64 after UTF-8, or decode it back. The result is not encryption.
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What a UUID Is, and How to Generate One
Generate 1 to 100 random UUID version 4 values. They are not sequential keys or passwords.
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How to Read a JWT Without Treating It as Verified
How to read a JWT header and payload, and why that does not verify the signature.
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How to Write a robots.txt File
What a robots.txt file tells crawlers, and why generating the text does not publish it.
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How to Read the Parts of a URL
How to read a URL's protocol, host, path, and query without encoding or tagging it.
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How to Write an Image Prompt Without Creating an Image
Build prompt stays in the browser and does not render an image. Generate with AI sends the brief to Gemini.
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How to Read a Writing-Pattern Check
Analyze writing stays in the browser. Analyze with AI sends the draft to Gemini. Neither result is an authorship verdict.
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How to Convert a Time Between Zones
How to convert the same instant between two time zones, without turning it into a Unix timestamp.
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How to Click Faster: Average CPS, Jitter and Butterfly Clicking
How to click faster: the average CPS, a CPS rating table, and how regular, jitter, butterfly, and drag clicking compare, plus mouse tips and wrist safety.
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