Calculation and Time

After cleaning hexadecimal input, reverse the byte order and output the result separated by spaces.

Calculation and Time

Extract 0 and 1 from the input and reverse them character by character; other characters are ignored.

Calculation and Time

Count business days within a range or calculate N business days from a date, with settings for endpoints, weekends, excluded days, and make-up workdays.

Calculation and Time

Determine whether the input year is a leap year according to the Gregorian rules for every 4 years, 100 years, and 400 years.

Calculation and Time

Use the clickable numeric keypad to perform basic arithmetic, percentages, positive and negative signs, memory, and history calculations, with keyboard input supported.

Calculation and Time

Convert negative integers between 2–36 bases, and view the signed value, unsigned value, and two’s complement for the selected bit width.

Calculation and Time

Use BigInt to accurately convert non-negative integers between 2–36 bases, and swap the input and output bases as needed.

Calculation and Time

Use BigInt to accurately convert signed integers of up to 4096 bits between 2 and 36 bases, with quick selection of commonly used bases.

Calculation and Time

Use the scientific keyboard to calculate powers, roots, logarithms, factorials, trigonometric and inverse trigonometric functions, and switch DEG/RAD.

Calculation and Time

Use BigInt to quickly compute integer a to the bth power modulo m.

Calculation and Time

Calculate PPI and pixel diagonal from horizontal pixels, vertical pixels, and screen diagonal inches.

Calculation and Time

Browse monthly or yearly calendar overviews, quickly return to today, select a date, and switch the start of the week.

Calculation and Time

Use Gregorian calendar calculations unaffected by time zones or daylight saving time to add or subtract years, months, and days, or calculate the interval between two dates.

Calculation and Time

Perform BigInt integer division on two integers and output the quotient and remainder separately.

Calculation and Time

Calculate expressions composed of hexadecimal integers, parentheses, and addition, subtraction, multiplication, division, and remainder operators, while outputting both decimal and hexadecimal results.

Calculation and Time

Read numbers separated by blanks, commas, or semicolons, sort them in ascending or descending numerical order, and remove duplicates if needed.

Calculation and Time

Split the text array by a custom delimiter, reverse the order of the elements, then merge them using the same delimiter.

Calculation and Time

Switch between random passwords, memorable passphrases, and PIN; securely generate, assess entropy, and copy or refresh with one click.

Calculation and Time

Use the browser’s cryptographically secure random source to generate integers, decimals, or unique samples, then copy or export the results.

Calculation and Time

Securely generate batches of tokens and identifier strings using alphanumeric characters, Hex, Base64URL, URL-safe, or a custom character set.

Calculation and Time

Use the browser’s cryptographically secure random source to shuffle the list without bias, then distribute it evenly by group count and copy the result; up to 500 people, 20 groups.

Calculation and Time

Use the browser’s cryptographic random source to determine the result from up to 100 options, then play a spinner animation for display only.

Calculation and Time

Display the sign-magnitude, ones’ complement, twos’ complement, and hexadecimal representations of integers at 8, 16, 32, or 64 bits wide.

Calculation and Time

Calibrate the countdown using an absolute deadline. Supports presets, pausing, adding time, fullscreen, and an end sound.

Calculation and Time

Set the target date and time in the local time zone, and display the remaining days, hours, minutes, and seconds using an absolute timestamp; supports background calibration and share links.

Calculation and Time

Time by focus, short break, and long break cycles, with support for custom durations, pause, skip, and drift correction using an absolute deadline.

Calculation and Time

Calculate percentages, proportions, reverse-calculate original values, rate of change, and percentage increases or decreases, with explicit handling of zero denominators.

Calculation and Time

Create an in-page alarm for today or one that repeats daily, with sound, a 5-minute snooze, and system notifications enabled only with user consent.

Calculation and Time

Provides start, pause, resume, lap, and reset functions with millisecond display.

Calculation and Time

Look up and convert between rwx permissions for the user, group, and others, and their three-digit octal representation.

Calculation and Time

Split and annotate Cron fields in 5 or 6 sections, explaining step values, ranges, and enum syntax; do not calculate the next run time.

Calculation and Time

Use browser crypto.randomUUID to batch-generate GUID/UUID.

Calculation and Time

Encode the input value as big-endian IEEE hexadecimal and binary bytes for Float32 or Float64 with the 754 format.

Calculation and Time

Validate IPv4 dotted addresses and generate their IPv4 mapped compressed and full hexadecimal forms of IPv6.

Calculation and Time

Generate local-administered, unicast MAC addresses using the browser’s random source; supports colon, hyphen, and plain hexadecimal formats.

Calculation and Time

Explicitly parse Unix timestamps as automatic, seconds, or milliseconds, and display UTC, local time, and a copyable result.

Calculation and Time

Perform bidirectional Gregorian and lunar calendar conversion locally in the browser for 1900–2100 based on fixed calendar data, with support for leap months.

Calculation and Time

Query fixed 1900–2100 lunar leap-month data; results are calculated from local calendar data and do not depend on the browser’s ICU.

Calculation and Time

Calculate the next execution time from Cron expressions with restricted 5/6 fields and IANA time zone.

Calculation and Time

Convert one local meeting time to multiple IANA time zones, with warnings for date changes and daylight saving time ambiguity.

Calculation and Time

Generate RFC 5545 ICS event files locally, with support for time zones, locations, descriptions, participants, and durations.

Calculation and Time

Calculate taxes, tips, service fees, and split bills among multiple people using integer smallest currency units, and display rounding differences.

Calculation and Time

Parse RFC 5545 ICS text, displaying VEVENT, TZID, UID, line breaks, escapes, and unknown properties.

Calculation and Time

Calculates the next occurrence within a limited RFC 5545 RRULE, supporting FREQ, INTERVAL, COUNT, UNTIL, BYDAY, and BYMONTHDAY.

Calculation and Time

Only reads navigator.storage.estimate(), displays usage, quota, available space, and the ratio, and does not write to any storage.

Calculation and Time

Use the current browser Intl API to display localized numbers, currencies, dates, relative time, lists, and locale fallback.

Calculation and Time

View Chinese Mainland 2020–2026 holiday data with official sources and version labels; 2027–2030 shows only dates that can be determined by the rules and marks them as estimated.

Calculation and Time

Calculate population and sample variance and standard deviation locally in the browser, and report invalid rows in CSV-delimited or whitespace-delimited input.

Calculation and Time

Convert between Chinese numerals, English numerals, Roman numerals, and spelled-out English numbers locally.

Calculation and Time