tzconv 1.1

command-line tool to convert a date and time to several time zones at once

tzconv: convert a date and time to several time zones at once

This Python package provides a small command-line utility to convert a YYYY-MM-DD HH:MM formatted date and time to several other time zones.

Installation

tzconv is available through PyPI:

$ python3 -m pip install tzconv

Alternatively, you can install it directly from the Codeberg Git repository:

$ git clone https://codeberg.org/gnyeki/tzconv
$ python3 -m pip install --user ./tzconv

Usage

Basic usage

tzconv uses the time zone information available through your operating system, so time zones have to be specified accordingly:

$ tzconv \
    -f America/New_York \
    -t America/Los_Angeles \
    -t America/Halifax \
    -t Asia/Karachi \
    -t Asia/Calcutta \
    "2023-04-25 10:00"
EDT: 2023-04-25 10:00 (America/New_York)
PDT: 2023-04-25 07:00 (America/Los_Angeles)
ADT: 2023-04-25 11:00 (America/Halifax)
PKT: 2023-04-25 19:00 (Asia/Karachi)
IST: 2023-04-25 19:30 (Asia/Calcutta)
$

If the date is omitted, it imputes today's date:

$ tzconv \
    -f America/New_York \
    -t America/Los_Angeles \
    -t America/Halifax \
    -t Asia/Karachi \
    -t Asia/Calcutta \
    "10:00"
EDT: 2023-04-20 10:00 (America/New_York)
PDT: 2023-04-20 07:00 (America/Los_Angeles)
ADT: 2023-04-20 11:00 (America/Halifax)
PKT: 2023-04-20 19:00 (Asia/Karachi)
IST: 2023-04-20 19:30 (Asia/Calcutta)
$

Daylight savings

Daylight savings can complicate conversions. However, thanks to the Python standard library, tzconv is aware of changes to daylight savings, and it infers the correct offsets. For example, in March 2023, New York switched to daylight savings two weeks earlier than Budapest. Notice the switch from EST/CET to EDT/CET, and finally to EDT/CEST:

$ tzconv -f America/New_York -t Europe/Budapest "2023-03-07 10:00"
EST: 2023-03-07 10:00 (America/New_York)
CET: 2023-03-07 16:00 (Europe/Budapest)
$ tzconv -f America/New_York -t Europe/Budapest "2023-03-14 10:00"
EDT: 2023-03-14 10:00 (America/New_York)
CET: 2023-03-14 15:00 (Europe/Budapest)
$ tzconv -f America/New_York -t Europe/Budapest "2023-03-28 10:00"
EDT: 2023-03-28 10:00 (America/New_York)
CEST: 2023-03-28 16:00 (Europe/Budapest)
$

Custom shell commands for common conversions

If you have a project that spans several time zones, it is convenient to define a command for it in your .bashrc, .zshrc, or equivalent dot file, depending on what shell you use. For example, if you are using zsh, you can add the following to ~/.zshrc:

project_tz() {
    tzconv \
        --from-tz America/New_York \
        --to-tz America/Los_Angeles \
        --to-tz America/Halifax \
        --to-tz Asia/Karachi \
        --to-tz Asia/Calcutta \
        "$*"
}

Now you can reload ~/.zshrc and use project_tz as a shell command:

$ . ~/.zshrc
$ project_tz 2023-04-25 10:00
EDT: 2023-04-25 10:00 (America/New_York)
PDT: 2023-04-25 07:00 (America/Los_Angeles)
ADT: 2023-04-25 11:00 (America/Halifax)
PKT: 2023-04-25 19:00 (Asia/Karachi)
IST: 2023-04-25 19:30 (Asia/Calcutta)
$