How do you calculate the number of days between two dates?

Convert both dates to a day count from a fixed point and subtract, which is what every calendar library does under the hood. Counting by hand, add the days left in the start month, the full months in between and the days into the end month, remembering 29 February in leap years.

Do you count the start day or the end day?

By default neither is counted in full: Monday to Wednesday is 2 days. Tick "Include end date" to get 3, which is how hotel nights are not counted but rental days and some legal notice periods are.

How many weekdays are between two dates?

Every full week contributes 5 weekdays; the leftover days depend on the weekday the span starts on. This tool does that calculation but does not subtract public holidays, which vary by country.

Why is a month not always 30 days here?

Because the result follows the calendar rather than an average. 15 January to 15 February is one month whether that is 31 days or, from 15 February to 15 March, 28 or 29 days.

Days Between Dates

The exact time between two dates, in days, weeks, months and years.

About Days Between Dates

A days between dates calculator counts the exact time from one date to another: total days, weeks, months, years, hours and the number of weekdays in between.

How to use

Pick a start date and an end date. The start date defaults to today, and the Swap button exchanges the two.
Tick "Include end date" to count both ends, the way deadlines and bookings are often counted.
Read the results, or copy any row. An end date earlier than the start is counted backwards and labelled "before".

What it does

Counts whole calendar days between the two dates, so daylight saving changes never produce a fractional day.
Breaks the span into weeks and days, months and days, and years, months and days, following the calendar: a month is the same date in the next month, and a span that starts on the 31st steps to the last day of a shorter month.
Counts the weekdays (Monday to Friday) in the span without any holiday calendar.
Shows which day of the week each date falls on.

Example

2024-01-31 → 2025-03-01
Total days: 395
Weeks: 56 weeks, 3 days
Years: 1 year, 1 month, 1 day
Weekdays: 283

Privacy

The dates are compared in the browser. No request is made, and nothing is stored.

Frequently asked questions

How do you calculate the number of days between two dates?: Convert both dates to a day count from a fixed point and subtract, which is what every calendar library does under the hood. Counting by hand, add the days left in the start month, the full months in between and the days into the end month, remembering 29 February in leap years.
Do you count the start day or the end day?: By default neither is counted in full: Monday to Wednesday is 2 days. Tick "Include end date" to get 3, which is how hotel nights are not counted but rental days and some legal notice periods are.
How many weekdays are between two dates?: Every full week contributes 5 weekdays; the leftover days depend on the weekday the span starts on. This tool does that calculation but does not subtract public holidays, which vary by country.
Why is a month not always 30 days here?: Because the result follows the calendar rather than an average. 15 January to 15 February is one month whether that is 31 days or, from 15 February to 15 March, 28 or 29 days.

Encode & decode

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ULID Generator: Sortable 26-character IDs with a time prefix.
Password Generator: Random passwords with length and character-set controls.
Hash Generator: MD5, SHA-1, SHA-256, SHA-384, SHA-512 and HMAC for text or a file.
Base64 Encoder / Decoder: Base64, Base32 and Base58 in both directions.
ROT13 / Caesar Cipher: Shift letters by any amount, or ROT13 in one click.
JWT Decoder: Read a token’s header and payload without sending it anywhere.
URL Encoder / Decoder: Percent-encode text for URLs, or decode it back.
HTML Entities: Escape &, < and > for HTML, or unescape them.
Base64 Image Encoder: Image to a Base64 data URL for CSS or HTML, or decode one back.
Random Number Generator: Random integers in a range, one or many, with or without repeats.
Bcrypt Generator: Hash a password with bcrypt, or check one against a hash.
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Morse Code Translator: Text to dots and dashes, and back.

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JSON to Kotlin: Infer Kotlin data classes from a JSON sample.
JSON to C# Class: Infer C# classes from a JSON sample.
Base Number Converter: Binary, octal, decimal, hex and any base up to 36.
Text ⇄ Binary / Hex: Text to binary, hex, octal or decimal, and back.
Unix ⇄ UTC: Epoch seconds or milliseconds to a readable date, and back.
Timezone Converter: Convert a time between cities, with DST handled.
Cron Converter: Describe a schedule in words and get the cron expression.
Cron Expression Parser: Explain a cron expression in words and list its next run times.
Days Between Dates: The exact time between two dates, in days, weeks, months and years.
Age Calculator: Exact age in years, months and days, and the next birthday.
Epoch Clock: The current Unix timestamp, live, in seconds and milliseconds.
CIDR / Subnet Calculator: Network, broadcast, mask and host count for an IPv4 CIDR block.
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Time Unit: Seconds, minutes, hours, days and beyond.
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Weight: Kilograms, pounds, ounces and stone.

Text & code

Lorem Ipsum Generator: Placeholder paragraphs, sentences or words.
Slug Generator: Turn a title into a URL-safe slug.
Text Compare: Diff by line, word or character, unified or side by side.
URL Parser: Break a URL into host, path, query and fragment.
JSON Formatter & Validator: Validate, pretty-print or minify JSON.
JSON Diff: Compare two JSON documents, ignoring key order and formatting.
JSONPath Tester: Query JSON with a JSONPath expression.
SQL Formatter: Format and indent SQL for any dialect.
JavaScript Beautifier: Format minified or messy JavaScript into readable code.
HTML Formatter: Indent and tidy HTML, or strip it down to one line.
XML Formatter: Pretty-print or minify XML, with error positions.
CSS Minifier / Beautifier: Minify CSS, or expand it back to readable rules.
HTML to Markdown: Convert HTML to clean Markdown.
Text Case Converter: camelCase, snake_case, kebab-case, Title Case and more.
Markdown Previewer: Render Markdown as you type.
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Duplicate Line Remover: Keep each line once.
String Counter: Characters, words, lines and bytes.
Regex Tester: Test a pattern against text with live matches.
Regex Cheatsheet: Regular-expression syntax with examples.

Word play

Palindrome Checker: Does it read the same backwards?
String Reverser / Rotator: Reverse a string or rotate it by n characters.
Roman Numeral Converter: 1984 ⇄ MCMLXXXIV.
NATO Phonetic Alphabet: Spell text out as Alfa, Bravo, Charlie.
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Leetspeak Translator: Text to l33t and back.
Word Frequency Counter: Which words appear most, and how often.

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Barcode / QR Reader: Decode a barcode or QR code from an image.
Color Picker: Pick a colour and copy it in every format.
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Contrast Checker: Contrast ratio of text on a background, against WCAG AA and AAA.
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Image Compressor: Shrink a JPEG, PNG or WebP in the browser.
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Reference

ASCII Table: Every ASCII character with its decimal, hex, octal, binary and HTML code.
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