Final Countdown JS is a library of React hooks to manage counters, timers and stopwatches.

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You can use npm, yarn or pnpm to install Final Countdown JS.

npm install final-countdown-js

yarn add final-countdown-js

pnpm install final-countdown-js

The useCountDown hook provides a simple countdown timer functionality.

It takes three arguments:

• min (number): the initial value of the counter.
• max(number): the final value of the counter. It has to be greater than min.
• options(optional object): the options for the counter.
  • startPaused (optional boolean): determines whether the counter should start in a paused state. Defaults to false.
  • onFinish (optional function): a function that will be called when the counter reaches the final value.

It returns an object with the following props:

• current: an object holding the current time of the counter in both leading zero and non-leading zero formats. This object has two properties:
  • withLeadingZero: a string indicating the current time of the counter with leading zeroes where necessary.
  • withoutLeadingZero: a string indicating the current time of the counter without leading zeros.
• isPaused: a boolean value indicating if the counter is currently paused.
• isOver: a boolean value indicating if the counter has finished running.
• pause: a function that, when called, will pause the counter.
• play: a function that, when called, will resume (or start) the counter.
• reset: a function that, when called, will reset the counter.
• togglePause: a function that, when called, will toggle between pausing and playing the counter.

Example:

import { useCountDown } from "final-countdown-js";

const ReactCounter = () => {
  const { current, isPaused, isOver, pause, play, reset, togglePause } =
    useCountDown(0, 10, {
      startPaused: false,
      onFinish: () => console.log("Counter ended"),
    });

  return (
    <div>
      <p>Counter value: {current.withLeadingZero}</p>
      <p>Counter value: {current.withoutLeadingZero}</p>
      <p>Is the counter paused? {isPaused ? "Yes" : "No"}</p>
      <p>Has the counter over? {isOver ? "Yes" : "No"}</p>
      <button onClick={pause}>Pause</button>
      <button onClick={play}>Play</button>
      <button onClick={reset}>Reset</button>
      <button onClick={togglePause}>Toggle Pause</button>
    </div>
  );
};

export default ReactCounter;

The useCountUp hook provides a simple countup timer functionality.

It takes three arguments:

• min (number): the initial value of the counter.
• max(number): the final value of the counter. It has to be greater than min.
• options(optional object): the options for the counter.
  • startPaused (optional boolean): determines whether the counter should start in a paused state. Defaults to false.
  • onFinish (optional function): a function that will be called when the counter reaches the final value.

It returns an object with the following props:

• current: an object holding the current time of the counter in both leading zero and non-leading zero formats. This object has two properties:
  • withLeadingZero: a string indicating the current time of the counter with leading zeroes where necessary.
  • withoutLeadingZero: a string indicating the current time of the counter without leading zeros.
• isPaused: a boolean value indicating if the counter is currently paused.
• isOver: a boolean value indicating if the counter has finished running.
• pause: a function that, when called, will pause the counter.
• play: a function that, when called, will resume (or start) the counter.
• reset: a function that, when called, will reset the counter.
• togglePause: a function that, when called, will toggle between pausing and playing the counter.

Example:

import { useCountUp } from "final-countdown-js";

const ReactCounter = () => {
  const { current, isPaused, isOver, pause, play, reset, togglePause } =
    useCountUp(0, 10, {
      startPaused: false,
      onFinish: () => console.log("Counter ended"),
    });

  return (
    <div>
      <p>Counter value: {current.withLeadingZero}</p>
      <p>Counter value: {current.withoutLeadingZero}</p>
      <p>Is the counter paused? {isPaused ? "Yes" : "No"}</p>
      <p>Has the counter over? {isOver ? "Yes" : "No"}</p>
      <button onClick={pause}>Pause</button>
      <button onClick={play}>Play</button>
      <button onClick={reset}>Reset</button>
      <button onClick={togglePause}>Toggle Pause</button>
    </div>
  );
};

export default ReactCounter;

The useStopwatch hook provides stopwatch functionality with or without a limit.

It takes one argument:

• options(optional object): the options for the stopwatch.
  • endTime (options string): specifies the time at which the stopwatch will stop. It must be in dd:hh:mm:ss format. If not specified, the stopwatch will not end.
  • startPaused (optional boolean): determines whether the stopwatch should start in a paused state. Defaults to false.
  • onFinish (optional function): a function that will be called when the stopwatch reaches the final value.
  • separator (optional string): specifies the separator to be used between days, hours, minutes, and seconds when the time is represented as a string. By default, colon (:) is used as a separator.

It returns an object with the following props:

• current: an object holding the current time of the stopwatch in both leading zero and non-leading zero formats. This object has two properties:
  • withLeadingZero: a string indicating the current time of the stopwatch with leading zeroes where necessary.
  • withoutLeadingZero: a string indicating the current time of the stopwatch without leading zeros.
• isPaused: a boolean value indicating if the stopwatch is currently paused.
• isOver: a boolean value indicating if the stopwatch has finished running.
• currentDays: a number indicating the current value of the days on the stopwatch.
• currentHours: a number indicating the current value of the hours on the stopwatch.
• currentMinutes: a number indicating the current value of the minutes on the stopwatch.
• currentSeconds: a number indicating the current value of the seconds on the stopwatch.
• elapsedSeconds: a number indicating the total elapsed time, calculated in seconds, since the stopwatch started.
• remainingSeconds: a number indicating the total remaining time, calculated in seconds, until the stopwatch reaches the initially set time. If endTime is not specified, it will always be 0.
• remainingTime: analogous to the current object, this object holds the remaining time in both formats:
  • withLeadingZero: a string indicating the remaining time with leading zeroes. If endTime is not specified, it will always be 00:00:00:00.
  • withoutLeadingZero: a string indicating the remaining time without leading zeroes. If endTime is not specified, it will always be 0:0:0:0.
• pause: a function that, when called, will pause the stopwatch.
• play: a function that, when called, will resume (or start) the stopwatch.
• reset: a function that, when called, will reset the stopwatch.
• togglePause: a function that, when called, will toggle between pausing and playing the stopwatch.

Example:

import { useStopwatch } from "final-countdown-js";

const ReactCounter = () => {
  const {
    current,
    remainingTime,
    currentDays,
    currentHours,
    currentMinutes,
    currentSeconds,
    elapsedSeconds,
    remainingSeconds,
    isPaused,
    isOver,
    pause,
    play,
    reset,
    togglePause,
  } = useStopwatch({
    endTime: "00:00:00:10",
    startPaused: true,
    separator: "-",
    onFinish: () => console.log("Stopwatch ended"),
  });

  return (
    <div>
      <p>Stopwatch value: {current.withLeadingZero}</p>
      <p>Stopwatch value: {current.withoutLeadingZero}</p>
      <p>Remaining time: {remainingTime.withLeadingZero}</p>
      <p>Remaining time: {remainingTime.withoutLeadingZero}</p>
      <p>Days: {currentDays}</p>
      <p>Hours: {currentHours}</p>
      <p>Minutes: {currentMinutes}</p>
      <p>Seconds: {currentSeconds}</p>
      <p>Elapsed seconds: {elapsedSeconds}</p>
      <p>Remaining seconds: {remainingSeconds}</p>
      <p>Is the counter paused? {isPaused ? "Yes" : "No"}</p>
      <p>Has the counter over? {isOver ? "Yes" : "No"}</p>
      <button onClick={pause}>Pause</button>
      <button onClick={play}>Play</button>
      <button onClick={reset}>Reset</button>
      <button onClick={togglePause}>Toggle Pause</button>
    </div>
  );
};

export default ReactCounter;

The useTimer hook provides timer functionality.

It takes two arguments:

• startTime (string): specifies the time at which the timer will start. It must be in dd:hh:mm:ss format.
• options(optional object): the options for the timer.
  • startPaused (optional boolean): determines whether the timer should start in a paused state. Defaults to false.
  • onFinish (optional function): a function that will be called when the timer reaches the final value.
  • separator (optional string): specifies the separator to be used between days, hours, minutes, and seconds when the time is represented as a string. By default, colon (:) is used as a separator.

It returns an object with the following props:

• current: an object holding the current time of the timer in both leading zero and non-leading zero formats. This object has two properties:
  • withLeadingZero: a string indicating the current time of the timer with leading zeroes where necessary.
  • withoutLeadingZero: a string indicating the current time of the timer without leading zeros.
• isPaused: a boolean value indicating if the timer is currently paused.
• isOver: a boolean value indicating if the timer has finished running.
• currentDays: a number indicating the current value of the days on the timer.
• currentHours: a number indicating the current value of the hours on the timer.
• currentMinutes: a number indicating the current value of the minutes on the timer.
• currentSeconds: a number indicating the current value of the seconds on the timer.
• elapsedSeconds: a number indicating the total elapsed time, calculated in seconds, since the timer started.
• remainingSeconds: a number indicating the total remaining time, calculated in seconds, until the timer reaches the initially set time.
• elapsedTime: analogous to the current object, this object holds the elapsed time in both formats:
  • withLeadingZero: a string indicating the elapsed time with leading zeroes.
  • withoutLeadingZero: a string indicating the elapsed time without leading zeroes.
• pause: a function that, when called, will pause the timer.
• play: a function that, when called, will resume (or start) the timer.
• reset: a function that, when called, will reset the timer.
• togglePause: a function that, when called, will toggle between pausing and playing the timer.

Example:

import { useTimer } from "final-countdown-js";

const ReactCounter = () => {
  const {
    current,
    elapsedTime,
    currentDays,
    currentHours,
    currentMinutes,
    currentSeconds,
    elapsedSeconds,
    remainingSeconds,
    isPaused,
    isOver,
    pause,
    play,
    reset,
    togglePause,
  } = useTimer("00:00:00:10", {
    startPaused: true,
    separator: "-",
    onFinish: () => console.log("Timer ended"),
  });

  return (
    <div>
      <p>Timer value: {current.withLeadingZero}</p>
      <p>Timer value: {current.withoutLeadingZero}</p>
      <p>Elapsed time: {elapsedTime.withLeadingZero}</p>
      <p>Elapsed time: {elapsedTime.withoutLeadingZero}</p>
      <p>Days: {currentDays}</p>
      <p>Hours: {currentHours}</p>
      <p>Minutes: {currentMinutes}</p>
      <p>Seconds: {currentSeconds}</p>
      <p>Elapsed seconds: {elapsedSeconds}</p>
      <p>Remaining seconds: {remainingSeconds}</p>
      <p>Is the counter paused? {isPaused ? "Yes" : "No"}</p>
      <p>Has the counter over? {isOver ? "Yes" : "No"}</p>
      <button onClick={pause}>Pause</button>
      <button onClick={play}>Play</button>
      <button onClick={reset}>Reset</button>
      <button onClick={togglePause}>Toggle Pause</button>
    </div>
  );
};

export default ReactCounter;

If you're interested in contributing to Final Countdown JS, please read our contributing docs before submitting a pull request.

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