Guides for everyday tasks
Practical guides covering our calculators, calendars, text tools and timers. Find an example, check the details, then open the tool.
76 guides
Calendar Days vs Business Days
Choose the right way to count days for a project, leave request or delivery estimate.
Read the guide ↗PRACTICAL GUIDEPlan a Meeting Across Time Zones
Compare named time zones on the actual meeting date and make the invitation unambiguous.
Read the guide ↗PRACTICAL GUIDEHours and Minutes to Decimal Hours
Understand why 7 hours 30 minutes is 7.50 hours, and avoid common timesheet errors.
Read the guide ↗PRACTICAL GUIDEHow to Read a World Clock Across Different Dates
Check the local date as well as the hour before calling someone in another time zone.
Read the guide ↗PRACTICAL GUIDECalculate Age in Years, Months and Days
Understand completed years, month-end birthdays and the difference between age and elapsed days.
Read the guide ↗PRACTICAL GUIDECount Days Between Two Dates Without an Off-by-One Error
Decide whether the final date counts before comparing a duration, trip or leave request.
Read the guide ↗PRACTICAL GUIDEAdd or Subtract Calendar Days from a Date
Move a date forward or backward and keep weekends, month lengths and leap years straight.
Read the guide ↗PRACTICAL GUIDEFind the Weekday for Any Calendar Date
Check birthdays, appointments and historical dates using a clear Gregorian date.
Read the guide ↗PRACTICAL GUIDEWhy an ISO Week Can Belong to a Different Year
Understand Monday-first ISO weeks and the January dates that fall in the previous week-year.
Read the guide ↗PRACTICAL GUIDEMeasure Time Since an Event
Choose an exact starting moment and understand the device-clock assumptions behind an elapsed-time counter.
Read the guide ↗PRACTICAL GUIDESet an Online Timer That Matches Your Task
Choose a duration, check sound settings and understand what happens when a browser tab sleeps.
Read the guide ↗PRACTICAL GUIDEPlan a Pomodoro Session Around One Clear Task
Use a focus timer to create a workable session, with a small goal and a deliberate break.
Read the guide ↗PRACTICAL GUIDERead Stopwatch Laps and Total Time
Separate an individual lap from cumulative elapsed time when comparing repeated activities.
Read the guide ↗PRACTICAL GUIDESet a Countdown with the Correct Date and Time Zone
Avoid a countdown that is a day or an hour out by defining the target moment clearly.
Read the guide ↗PRACTICAL GUIDEPrint a Monthly Calendar with the Right Holiday Marks
Choose a month, week layout and holiday scope before saving a clean calendar as PDF.
Read the guide ↗PRACTICAL GUIDEMake a Printable Year Planner
Use a twelve-month overview for broad planning, then keep the details in a monthly view.
Read the guide ↗PRACTICAL GUIDEUnix Timestamps: Seconds, Milliseconds and Local Time
Identify the timestamp unit before converting a log entry or spreadsheet value.
Read the guide ↗PRACTICAL GUIDERead Roman Numerals and Check Standard Notation
Learn additive and subtractive pairs with examples you can verify in both directions.
Read the guide ↗PRACTICAL GUIDEPercentage Change, Percentage Points and Percent of a Number
Choose the calculation that matches the comparison instead of treating every percent question alike.
Read the guide ↗PRACTICAL GUIDEConvert Units Without Mixing Different Quantities
Check the measurement family, direction and precision before using a converted number.
Read the guide ↗PRACTICAL GUIDEWord Counts, Character Counts and Text Limits
Understand why a browser count may differ from the limit shown by a publishing platform.
Read the guide ↗PRACTICAL GUIDEChinese Calendar Dates and Leap Months
Understand why a Chinese calendar month cannot be replaced by a fixed Gregorian date.
Read the guide ↗PRACTICAL GUIDEHijri Conversion and Local Moon-Sighting Dates
Know what a calculated calendar conversion can tell you, and what still needs a local announcement.
Read the guide ↗PRACTICAL GUIDEPrepare the Inputs for a Simple Zakat Estimate
Keep values in one currency and understand the limits of a monetary-assets calculator.
Read the guide ↗PRACTICAL GUIDEPublic Holidays, Regional Dates and Observances
Read holiday lists without assuming that every listed date closes every workplace.
Read the guide ↗PRACTICAL GUIDEChoose a City, Prayer Method and Asr School
Check the three settings that most often explain differences between prayer timetables.
Read the guide ↗PRACTICAL GUIDEPrint and Check a Monthly Prayer Timetable
Keep the city, method, school and time zone with every saved or shared timetable.
Read the guide ↗PRACTICAL GUIDEPrepare Your Ramadan 2027 Calendar (1448 AH)
Find a city-specific sehri and iftar timetable for the upcoming Ramadan and keep calculated dates provisional.
Read the guide ↗PRACTICAL GUIDERead Sunrise, Sunset and Moon Phase Estimates
Understand coordinates, time zones and the difference between an astronomical estimate and a local observation.
Read the guide ↗PRACTICAL GUIDEDaylight Saving: Missing and Repeated Local Times
Handle a clock-change date without silently choosing the wrong instant.
Read the guide ↗PRACTICAL GUIDECompare Sale Prices and Stacked Discounts
A discount is only one part of an offer.
Read the guide ↗PRACTICAL GUIDESplit a Restaurant Bill Without Losing the Remainder
Check whether the bill already contains a service charge and what amount your group wants to use for the tip.
Read the guide ↗PRACTICAL GUIDEExtract Included Tax Using the Correct Base
A displayed price may be a pre-tax amount or a final tax-inclusive amount.
Read the guide ↗PRACTICAL GUIDEMargin and Markup Use Different Starting Points
Use the cost and selling price for the same quantity of the same product.
Read the guide ↗PRACTICAL GUIDESplit a Total in a Given Ratio
A 3:2 split has five combined parts.
Read the guide ↗PRACTICAL GUIDEChoose Between the Mean and the Median
Put comparable measurements into the same list and use consistent units.
Read the guide ↗PRACTICAL GUIDEAdd Fractions Without Adding Their Denominators
A half and a third are different-sized parts.
Read the guide ↗PRACTICAL GUIDERead Powers of Ten and E Notation
A scientific-notation number has a coefficient multiplied by a power of ten.
Read the guide ↗PRACTICAL GUIDEConvert Binary and Hexadecimal Values Safely
The digits 10 mean ten in decimal but two in binary.
Read the guide ↗PRACTICAL GUIDEUse Common Factors and Common Multiples
The greatest common divisor is the largest positive integer that divides both inputs without a remainder.
Read the guide ↗PRACTICAL GUIDEChoose a Rounding Rule Before Rounding
Zero decimal places rounds to a whole number.
Read the guide ↗PRACTICAL GUIDESample Random Integers with or Without Repeats
Both endpoints are included.
Read the guide ↗PRACTICAL GUIDEMeasure a Rectangular Area Before Ordering Materials
Use the same unit for length and width.
Read the guide ↗PRACTICAL GUIDEAverage Speed Depends on Total Elapsed Time
Enter kilometres and minutes in the fields provided.
Read the guide ↗PRACTICAL GUIDECompare Fuel Economy Across Different Units
A US gallon and an imperial gallon are not the same volume.
Read the guide ↗PRACTICAL GUIDEWhy a GB and a GiB Give Different Numbers
A decimal gigabyte contains one billion bytes.
Read the guide ↗PRACTICAL GUIDEResize Dimensions Without Stretching an Image
A 16:9 landscape image and a 9:16 portrait image have reversed proportions.
Read the guide ↗PRACTICAL GUIDERead Display Density Without Confusing It with Size
Two screens can have the same pixel count but different physical dimensions.
Read the guide ↗PRACTICAL GUIDEAdd Hours and Minutes Using Base 60
A duration describes an amount of elapsed time.
Read the guide ↗PRACTICAL GUIDEEstimate Reading Time with a Pace That Fits the Task
Include the headings and captions that belong to the reading task.
Read the guide ↗PRACTICAL GUIDEChange Capitalization Without Losing Meaning
Uppercase and lowercase are useful for a uniform list or heading.
Read the guide ↗PRACTICAL GUIDEClean a List Without Changing Its Original Order
The tool compares whole lines, not individual words or spreadsheet columns.
Read the guide ↗PRACTICAL GUIDEChoose Numeric or Text Sorting for a List
Numbers stored as text can sort differently from numerical values.
Read the guide ↗PRACTICAL GUIDEClean Whitespace Without Damaging the Structure
Extra spaces in prose can be distracting, while indentation in source code can be meaningful.
Read the guide ↗PRACTICAL GUIDECompare Text Versions and Read a Line Diff
Put the earlier version on the original side and the later version on the revised side.
Read the guide ↗PRACTICAL GUIDEFormat JSON Without Confusing Syntax and Validation
Property names and string values need double quotes.
Read the guide ↗PRACTICAL GUIDEEncode a Query Value Without Breaking URL Separators
A query value can contain spaces, ampersands or other characters with special URL meanings.
Read the guide ↗PRACTICAL GUIDEUse Base64 for Representation, Not Secrecy
Base64 represents bytes using a text alphabet.
Read the guide ↗PRACTICAL GUIDEEscape HTML Characters in the Right Context
An angle bracket can start markup in an HTML document.
Read the guide ↗PRACTICAL GUIDEMove Between HEX, RGB and HSL Colour Values
A six-digit HEX value uses two hexadecimal digits for each red, green and blue channel.
Read the guide ↗PRACTICAL GUIDEGet a Repeatable SHA Hash From Text
Calculate SHA-256, SHA-384 or SHA-512 hashes of UTF-8 text directly in your browser.
Read the guide ↗PRACTICAL GUIDEUse Random UUIDs as Identifiers
Generate one or a batch of random version 4 UUIDs using your browser’s cryptographic random source.
Read the guide ↗PRACTICAL GUIDERead JWT Claims Without Mistaking Decoding for Verification
Inspect a three-part JWT’s header, payload and UTC claim dates without uploading the token.
Read the guide ↗PRACTICAL GUIDEConvert JSON Records Into a CSV Table
Turn a JSON array of objects into CSV, with quoted fields and optional spreadsheet formula protection.
Read the guide ↗PRACTICAL GUIDEKeep CSV Values Intact When Converting to JSON
Convert CSV headers and rows into JSON objects while preserving leading zeros and large identifiers as strings.
Read the guide ↗PRACTICAL GUIDERead Query Strings Without Losing Repeated Parameters
Inspect URL query parameters in order, including repeated keys, empty values and decoded form-query text.
Read the guide ↗PRACTICAL GUIDECheck the UTF-8 Bytes Behind a String
Encode text as hexadecimal UTF-8 bytes or decode a hex byte sequence back to text.
Read the guide ↗PRACTICAL GUIDEFind Hidden Differences in Unicode Text
See code points, UTF-16 length and UTF-8 bytes to investigate invisible characters and text differences.
Read the guide ↗PRACTICAL GUIDEEscape Text for a JSON String Value
Convert plain text into a JSON string literal or decode a quoted JSON string back into plain text.
Read the guide ↗PRACTICAL GUIDEEstimate Text Payload Size in UTF-8
Measure UTF-8 bytes, Unicode code points and UTF-16 code units before sending or storing text.
Read the guide ↗PRACTICAL GUIDEGenerate and Store a Unique Password
Create random passwords locally with configurable length, symbols and a browser cryptographic random source.
Read the guide ↗PRACTICAL GUIDEChoose a Readable Slug and Keep Its URL Stable
Turn a heading into a lowercase, hyphen-separated slug with ASCII or Unicode letter support.
Read the guide ↗PRACTICAL GUIDEFind an Exact Value With JSON Pointer
Select a value from a JSON document using a standard slash-separated JSON Pointer.
Read the guide ↗PRACTICAL GUIDECompare JSON Values Instead of Formatting
Compare two JSON values structurally, ignoring object key order while retaining array order and value types.
Read the guide ↗PRACTICAL GUIDERead HTTP Headers Without Combining the Wrong Fields
Read pasted HTTP headers as ordered fields and grouped names while retaining repeated values.
Read the guide ↗PRACTICAL GUIDEPublish CSV Data as an Accessible HTML Table
Generate escaped HTML table source from CSV, including column headers and a simple semantic structure.
Read the guide ↗