Ruby on Rails Time, Date, DateTime Cheatsheet

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Rails has a lot of handy methods built-in that sometimes all you have to do is know it. In consequence, there are an overwhelming methods available to get specific time and/or date.

This cheatsheet should provide some practical methods for Time, Date, DateTime that may help you in developing with Rails. I have also included an example output of each method so you don't have to manually enter it in rails console to know what the outcome would be.

Here is a brief overview of what methods will be covered in this cheatsheet. Feel free to skip to the methods that you need or scroll around to know what methods there are. Maybe it will help you in the future. Enjoy!

  • Current time and date (now, current, today)
  • Specific day (yesterday, tomorrow)
  • Specific moment in time (beginning_of_minute, end_of_minute, beginning_of_hour, end_of_hour)
  • Specific time of the day (beginning_of_day, middle_of_day, end_of_day)
  • Specific time of a week (beginning_of_week, end_of_week, last_week, next_week, last_weekday, next_weekday)
  • Specific time of a month (beginning_of_month, end_of_month, last_month, next_month)
  • Specific time of a quarter (beginning_of_quarter, end_of_quarter, last_quarter, next_quarter)
  • Specific time of a year (beginning_of_year, end_of_year, last_year, next_year)

Current time and date

Each classes have its own methods to get the current time or date.

Time

For Time, it has now. It returns current date and time. Do notice that it automatically gives it in local time (with local timezone offset). 

Time.now // 2021-04-17 20:19:39.22369 +0700

Date

For Date, it has current and today. It returns date with the month and day's shorten name. 

Date.current // Sat, 17 Apr 2021
Date.today   // Sat, 17 Apr 2021

DateTime

DateTime has both now and current method. Both returns Date's date style and Time's time style. The difference is now gives the local time and current gives time in UTC. 

DateTime.now     // Sat, 17 Apr 2021 20:24:54 +0700
DateTime.current // Sat, 17 Apr 2021 13:24:58 +0000
Heads up!

All the following methods can be called with any Time, Date, and DateTime's instance.

Let's say you fetched a date/time/datetime from a database. You can find specific day relative to that time.

For each example, I have provided the relative time/date/datetime of when the Time.now, Date.current, DateTime.current, and DateTime.now was invoked.

Specific day

Let's say you want to get yesterday's or tomorrow's date. Date and DateTime has the method of yesterday and tomorrow. 

// Current's date: Sat, 17 Apr 2021

Date.yesterday     // Fri, 16 Apr 2021
DateTime.yesterday // Fri, 16 Apr 2021

Date.tomorrow      // Sun, 18 Apr 2021
DateTime.tomorrow  // Sun, 18 Apr 2021

Specific moment in time

For specific moment in a defined time, Time and DateTime has several methods.

beginning_of_minute

beginning_of_minute returns a time's start of minute.

// Current time: Sat, 17 Apr 2021 21:11:30 +0700

Time.now.beginning_of_minute
// 2021-04-17 21:11:00 +0700

DateTime.now.beginning_of_minute
// Sat, 17 Apr 2021 21:11:00 +0700

DateTime.current.beginning_of_minute
// Sat, 17 Apr 2021 14:11:00 +0000

end_of_minute

end_of_minute returns a time's end of minute.

// Current time: Sat, 17 Apr 2021 21:11:30 +0700

Time.now.end_of_minute
// 2021-04-17 21:11:59.999999999 +0700

DateTime.now.end_of_minute
// Sat, 17 Apr 2021 21:11:59 +0700

DateTime.current.end_of_minute
// Sat, 17 Apr 2021 14:11:59 +0000

beginning_of_hour

beginning_of_hour returns a time's start of hour.

// Current time: Sat, 17 Apr 2021 21:11:30 +0700

Time.now.beginning_of_hour
// 2021-04-17 21:00:00 +0700

DateTime.now.beginning_of_hour
// Sat, 17 Apr 2021 21:00:00 +0700

DateTime.current.beginning_of_hour
// Sat, 17 Apr 2021 14:00:00 +0000

end_of_hour

end_of_hour returns a time's end of hour.

// Current time: Sat, 17 Apr 2021 21:11:30 +0700

Time.now.end_of_hour
// 2021-04-17 21:59:59.999999999 +0700

DateTime.now.end_of_hour
// Sat, 17 Apr 2021 21:59:59 +0700

DateTime.current.end_of_hour
// Sat, 17 Apr 2021 14:59:59 +0000

Specific time of the day

All classes have beginning_of_day, middle_of_day, and end_of_day to instantly get a specific time of a defined date and time.

beginning_of_day

beginning_of_day gives time at 12 pm (midnight).

It is also aliased as:

  • midnight
  • at_midnight
  • at_beginning_of_day
// Current's date: Sat, 17 Apr 2021

Time.now.beginning_of_day
// 2021-04-17 00:00:00 +0700

Date.current.beginning_of_day
// Sat, 17 Apr 2021 00:00:00 UTC +00:00

DateTime.now.beginning_of_day
// Sat, 17 Apr 2021 00:00:00 +0700

DateTime.current.beginning_of_day
Sat, 17 Apr 2021 00:00:00 +0000

middle_of_day

middle_of_day gives time at 12 pm (noon/midday).

It also aliased as

  • midday
  • noon
  • at_midday
  • at_noon
  • at_middle_of_day
// Current's date: Sat, 17 Apr 2021

Time.now.middle_of_day
// 2021-04-17 12:00:00 +0700

Date.current.middle_of_day
// Sat, 17 Apr 2021 12:00:00 UTC +00:00

DateTime.now.middle_of_day
// Sat, 17 Apr 2021 12:00:00 +0700

DateTime.current.middle_of_day
// Sat, 17 Apr 2021 12:00:00 +0000

end_of_day

end_of_day returns time at 11.59 pm. It is also aliased as at_end_of_day. 

// Current's date: Sat, 17 Apr 2021

Time.now.end_of_day
// 2021-04-17 23:59:59.999999999 +0700

Date.current.end_of_day
// Sat, 17 Apr 2021 23:59:59 UTC +00:00

DateTime.now.end_of_day
// Sat, 17 Apr 2021 23:59:59 +0700

DateTime.current.end_of_day
// Sat, 17 Apr 2021 23:59:59 +0000

Specific day in a week

Rails have interesting methods for get a specific day based on a week. One thing to note that a week starts on Monday and ends on Sunday.

beginning_of_week

beginning_of_week returns the date of the first day of the week (Monday) and beginning of day in a time's week. 

// Current date: Sat, 17 Apr 2021

Time.now.beginning_of_week
// 2021-04-12 00:00:00 +0700

Date.current.beginning_of_week
// Mon, 12 Apr 2021

DateTime.current.beginning_of_week
// Mon, 12 Apr 2021 00:00:00 +0000

DateTime.now.beginning_of_week
// Mon, 12 Apr 2021 00:00:00 +0700

end_of_week

end_of_week returns date of the last day of the week (Sunday) and end of day in a time's week. It is also aliased as at_end_of_week. 

// Current date: Sat, 17 Apr 2021

Time.now.end_of_week
// 2021-04-18 23:59:59.999999999 +0700

Date.current.end_of_week
// Sun, 18 Apr 2021

DateTime.current.end_of_week
// Sun, 18 Apr 2021 23:59:59 +0000

DateTime.now.end_of_week
// Sun, 18 Apr 2021 23:59:59 +0700

last_week

last_week returns the beginning of the previous week. It is also aliased as prev_week. 

// Current date: Sat, 17 Apr 2021

Time.now.last_week
// 2021-04-05 00:00:00 +0700

Date.current.last_week
// Mon, 05 Apr 2021

DateTime.current.last_week
// Mon, 05 Apr 2021 00:00:00 +0000

DateTime.now.last_week
// Mon, 05 Apr 2021 00:00:00 +0700

next_week

next_week returns the beginning of the following week.

// Current date: Sat, 17 Apr 2021

Time.now.next_week
// 2021-04-19 00:00:00 +0700

Date.current.next_week
// Mon, 19 Apr 2021

DateTime.current.next_week
// Mon, 19 Apr 2021 00:00:00 +0000

DateTime.now.next_week
// Mon, 19 Apr 2021 00:00:00 +0700

last_weekday

last_weekday returns the last day of weekday and beginning of time from the defined time. It is also aliased as prev_weekday.

On a weekend's date (Saturday and Sunday), last_weekday returns Friday of the current week. 

// Current time: Sun, 18 Apr 2021 07:48:44 +0000

Time.now.last_weekday
// 2021-04-16 14:48:44.26745 +0700

Date.current.last_weekday
// Fri, 16 Apr 2021

DateTime.current.last_weekday
// Fri, 16 Apr 2021 07:48:44 +0000

DateTime.now.last_weekday
// Fri, 16 Apr 2021 14:48:44 +0700

On a weekday, last_weekday returns yesterday or Friday of the previous week if it was a Monday's date. 

// Current time: Fri, 16 Apr 2021 07:48:44 +0000

Time.now.last_weekday
// 2021-04-16 14:48:44.981865 +0700

Date.current.last_weekday
// Thu, 15 Apr 2021

DateTime.current.last_weekday
// Thu, 15 Apr 2021 07:48:44 +0000

DateTime.now.last_weekday
// Thu, 15 Apr 2021 14:48:44 +0700

// Current time: Mon, 12 Apr 2021 07:48:44 +0000

Time.now.last_weekday
// 2021-04-16 14:48:44.708858 +0700

Date.current.last_weekday
// Fri, 09 Apr 2021

DateTime.current.last_weekday
// Fri, 09 Apr 2021 07:48:44 +0000

DateTime.now.last_weekday
// Fri, 09 Apr 2021 14:48:44 +0700

next_weekday

next_weekday returns the next weekday of the defined time. It generally follows the same rules as last_weekday 

// Current time: Sun, 18 Apr 2021 07:48:44 +0000

Time.now.next_weekday
// 2021-04-19 14:48:44.758617 +0700

Date.current.next_weekday
// Mon, 19 Apr 2021

DateTime.current.next_weekday
// Mon, 19 Apr 2021 07:48:44 +0000

DateTime.now.next_weekday
// Mon, 19 Apr 2021 14:48:44 +0700

// Current time: Mon, 12 Apr 2021 07:48:44 +0000

Time.now.next_weekday
// 2021-04-12 14:48:44.24809 +0700

Date.current.next_weekday
// Tue, 13 Apr 2021

DateTime.current.next_weekday
// Tue, 13 Apr 2021 07:48:44 +0000

DateTime.now.next_weekday
// Tue, 13 Apr 2021 14:48:44 +0700

// Current time: Fri, 16 Apr 2021 07:48:44 +0000

Time.now.next_weekday
// 2021-04-19 14:48:44.465501 +0700

Date.current.next_weekday
// Mon, 19 Apr 2021

DateTime.current.next_weekday
// Mon, 19 Apr 2021 07:48:44 +0000

DateTime.now.next_weekday
// Mon, 19 Apr 2021 14:48:44 +0700

Specific time in a month

beginning_of_month

beginning_of_month returns the first day of the month dan its beginning of day. It is also aliased as at_beginning_of_month 

// Current date: Sun, 18 Apr 2021

Time.now.beginning_of_month
// 2021-04-01 00:00:00 +0700

Date.current.beginning_of_month
// Thu, 01 Apr 2021

DateTime.current.beginning_of_month
// Thu, 01 Apr 2021 00:00:00 +0000

DateTime.now.beginning_of_month
// Thu, 01 Apr 2021 00:00:00 +0700

end_of_month

end_of_month returns the last date of the month and its end of day time. It is also aliased as at_end_of_month. 

// Current date: Sun, 18 Apr 2021

Time.now.end_of_month
// 2021-04-30 23:59:59.999999999 +0700

Date.current.end_of_month
// Fri, 30 Apr 2021

DateTime.current.end_of_month
// Fri, 30 Apr 2021 23:59:59 +0000

DateTime.now.end_of_month
// Fri, 30 Apr 2021 23:59:59 +0700

last_month

Date & DateTime #last_month (alias prev_month) 

// Current time: Sun, 18 Apr 2021 08:29:19 +0000

Time.now.last_month
// 2021-03-18 15:29:19.529931 +0700

Date.current.last_month
// Thu, 18 Mar 2021

DateTime.current.last_month
// Thu, 18 Mar 2021 08:29:19 +0000

DateTime.now.last_month
// Thu, 18 Mar 2021 15:29:19 +0700

next_month

Date & DateTime #next_month

// Current time: Sun, 18 Apr 2021 08:29:19 +0000

Time.now.next_month
// 2021-05-18 15:29:19.529931 +0700

Date.current.next_month
// Tue, 18 May 2021

DateTime.current.next_month
// Tue, 18 May 2021 08:29:19 +0000

DateTime.now.next_month
// Tue, 18 May 2021 15:29:19 +0700

Specific time in a quarter

Sometimes we need quarterly period of a certain time. Rails has the usual beginning-end and last-next for quarters too.

beginning_of_quarter

beginning_of_quarter returns the first day of the quarter's month and its beginning of day's time. 

// Current date: Sun, 18 Apr 2021

Time.now.beginning_of_quarter
// 2021-04-01 00:00:00 +0700

Date.current.beginning_of_quarter
// Thu, 01 Apr 2021

DateTime.current.beginning_of_quarter
// Thu, 01 Apr 2021 00:00:00 +0000

DateTime.now.beginning_of_quarter
// Thu, 01 Apr 2021 00:00:00 +0700

end_of_quarter

end_of_quarter returns the last day of the quarter's month and its end of day's time. 

// Current date: Sun, 18 Apr 2021

Time.now.end_of_quarter
// 2021-06-30 23:59:59.999999999 +0700

Date.current.end_of_quarter
// Wed, 30 Jun 2021

DateTime.current.end_of_quarter
// Wed, 30 Jun 2021 23:59:59 +0000

DateTime.now.end_of_quarter
// Wed, 30 Jun 2021 23:59:59 +0700

prev_quarter

prev_quarter returns previous quarter's date and time relative to a defined time. 

// Current time: Sun, 18 Apr 2021 13:10:35 +0000

Time.now.prev_quarter
// 2021-01-18 20:10:35.383998 +0700

Date.current.prev_quarter
// Mon, 18 Jan 2021

DateTime.current.prev_quarter
// Mon, 18 Jan 2021 13:10:35 +0000

DateTime.now.prev_quarter
// Mon, 18 Jan 2021 20:10:35 +0700

next_quarter

next_quarter returns the next quarter's date and time relative to a defined time. 

// Current time: Sun, 18 Apr 2021 13:10:35 +0000

Time.now.next_quarter
// 2021-07-18 20:10:35.383998 +0700

Date.current.next_quarter
// Sun, 18 Jul 2021

DateTime.current.next_quarter
// Sun, 18 Jul 2021 13:10:35 +0000

DateTime.now.next_quarter
// Sun, 18 Jul 2021 20:10:35 +0700

Specific time in a year

Similar to monthly or quarterly date and time, there is also for yearly duration.

beginning_of_year

beginning_of_year returns the year's first date and beginning of day's time. 

// Current date: Sun, 18 Apr 2021

Time.now.beginning_of_year
// 2021-01-01 00:00:00 +0700

Date.current.beginning_of_year
// Fri, 01 Jan 2021

DateTime.current.beginning_of_year
// Fri, 01 Jan 2021 00:00:00 +0000

DateTime.now.beginning_of_year
// Fri, 01 Jan 2021 00:00:00 +0700

end_of_year

end_of_year returns the year's last date and end of day's time. 

// Current date: Sun, 18 Apr 2021

Time.now.end_of_year
// 2021-12-31 23:59:59.999999999 +0700

Date.current.end_of_year
// Fri, 31 Dec 2021

DateTime.current.end_of_year
// Fri, 31 Dec 2021 23:59:59 +0000

DateTime.now.end_of_year
// Fri, 31 Dec 2021 23:59:59 +0700

last_year

last_year returns the date of last year relative to a defined time. 

// Current time: Sun, 18 Apr 2021 13:20:58 +0000

Time.now.last_year
// 2020-04-18 20:20:58.898767 +0700

Date.current.last_year
// Sat, 18 Apr 2020

DateTime.current.last_year
// Sat, 18 Apr 2020 13:20:58 +0000

DateTime.now.last_year
// Sat, 18 Apr 2020 20:20:58 +0700

next_year

next_year returns the date of the following year relative to a defined time. 

// Current time: Sun, 18 Apr 2021 13:20:58 +0000

Time.now.next_year
// 2021-04-18 20:20:58.898767 +0700

Date.current.next_year
// Mon, 18 Apr 2022

DateTime.current.next_year
// Mon, 18 Apr 2022 13:20:58 +0000

DateTime.now.next_year
// Mon, 18 Apr 2022 20:20:58 +0700


If you want to know all methods that is available or not available to each classes, I have compiled a table of methods from Rails Date, Time, and DateTime's documentation. You can also see aliases for the methods. It's not perfect but it is somewhere to start rather than manually comparing it in Rails's (sometimes incomplete) documentation.

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