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Migrate from Date to Temporal

HowTo Replace Date

JavaScript Temporal was designed to replace the old Date object .

For new JavaScript projects, Temporal is the modern choice .

Temporal provides safer and clearer alternatives to Date patterns.

Temporal handles time zones correctly.

Temporal avoids mutation and simplifies date math .

This chapter shows how to migrate from Date code to modern Temporal code.

Replace new Date()

With Date, you create a date like this:

Date Example

const d = new Date();

With Temporal, choose the type you need.

Temporal Example

const instant = Temporal.Now.instant();

Use PlainDate if you only need a date.

Temporal Date Only

const today = Temporal.Now.plainDateISO();

Replace Date.now()

Date provides timestamps in milliseconds.

Date Example

const timestamp = Date.now();

With Temporal, use Instant .

Temporal Example

const now = Temporal.Now.instant();
const timestamp = instant.epochMilliseconds);

Replace getFullYear(), getMonth(), getDate()

Date uses getter methods.

Date Example

const d = new Date();
let year = d.getFullYear();
let month = d.getMonth();
let day = d.getDate();

Temporal exposes properties directly.

Temporal Example

const date = Temporal.Now.plainDateISO();
let year = date.year;
let month = date.month;
let day = date.day;

Months start at 1, not 0.

Replace setDate() and Other Mutating Methods

Date changes the original object.

Date Example

const d = new Date("2026-05-17");
d.setDate(d.getDate() + 7);

Temporal does not mutate values.

Temporal Example

const date = Temporal.PlainDate.from("2026-02-17");
const nextWeek = date.add({ days: 7 });

Replace Date Arithmetic

Date often requires manual millisecond calculations.

Date Example

const start = new Date("2026-05-01");
const end = new Date("2026-05-17");
const duration = end - start;

Temporal provides built-in duration calculations.

Temporal Example

const start = Temporal.PlainDate.from("2026-05-01");
const end = Temporal.PlainDate.from("2026-05-17");
const duration = start.until(end);

Replace Time Zone Handling

Date mixes local time and UTC.

This makes time zone handling confusing.

Date Example

let d = new Date();
let time1 = d.toString();
let time2 = d.toUTCString();

Temporal uses ZonedDateTime for clear time zone handling.

Temporal Example

const zoned = Temporal.Now.zonedDateTimeISO();

Convert Date to Temporal

You can convert an existing Date to a Temporal Instant.

Example

const d = new Date();
const instant = Temporal.Instant.fromEpochMilliseconds(d.getTime());

Where to Replace Date with Temporal

  • Use Temporal for new applications.
  • Use Temporal when time zones matter.
  • Use Temporal when doing date arithmetic.
  • Use Date if you must support older environments.

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1. JavaScript Objects2. JavaScript Temporal Tutorial3. JavaScript Loops4. JavaScript Advanced Functions5. JavaScript Objects6. JavaScript Temporal Intro7. JavaScript Iterables8. JavaScript Function Definitions9. JavaScript Object Properties10. JavaScript Temporal vs Date11. JavaScript Iterators12. JavaScript Callbacks13. JavaScript Object Methods14. JavaScript Temporal Duration15. JavaScript Generators16. The JavaScript this Keyword17. JavaScript this Keyword18. JavaScript Temporal Instant19. JavaScript Function call()20. JavaScript Display Objects21. JavaScript PlainDateTime22. JavaScript Function apply()23. JavaScript Object Constructors24. JavaScript Temporal PlainDate25. JavaScript Function bind()26. JavaScript PlainYearMonth27. Self-Invoking Functions28. JavaScript PlainMonthDay29. JavaScript Closures30. JavaScript Temporal PlainTime31. JavaScript Objects - Advanced32. JavaScript ZonedDateTime33. JavaScript Object Definitions34. JavaScript Temporal Now35. this in JavaScript Objects36. JS Temporal Arithmetic37. JavaScript Object Iterations38. JS Temporal Differences39. JavaScript Object Accessors40. JS Temporal Compare41. JavaScript Object Management42. JavaScript Temporal Conversion43. JavaScript Object Protection44. Temporal Display Formats45. JavaScript Object Prototypes46. JavaScript Temporal Mistakes47. JavaScript Classes48. Migrate from Date to Temporal49. JavaScript Class Inheritance50. Temporal Standards51. JavaScript Static Methods52. Asynchronous JavaScript53. Asynchronous Programming54. JavaScript Timeouts55. JavaScript Callbacks56. JavaScript Promises57. JavaScript async and await58. JavaScript fetch API59. Debugging Async JavaScript60. JavaScript Modules61. JavaScript Modules Export62. JavaScript Modules Import63. JS Module Namespace64. JavaScript Dynamic Modules65. JavaScript Meta Programming66. JavaScript Reflect67. JavaScript Proxy68. JavaScript Typed Arrays69. Typed Array Methods70. JavaScript ArrayBuffer71. JavaScript DataView72. JavaScript Atomics73. JavaScript HTML DOM Navigation74. JavaScript HTML DOM Elements (Nodes)75. JavaScript HTML DOM Collections76. JavaScript HTML DOM Node Lists77. JavaScript Window - The Browser Object Model78. JavaScript Window Screen79. JavaScript Window Location80. JavaScript Window History81. JavaScript Window Navigator82. JavaScript Popup Boxes83. JavaScript Timing Events84. JavaScript Cookies85. Web APIs - Introduction86. JavaScript Fetch API87. Web Geolocation API88. Web History API89. Pointer Events API90. Web Storage API91. JavaScript Validation API92. Web Workers API93. AJAX Introduction94. AJAX - The XMLHttpRequest Object95. AJAX - XMLHttpRequest96. AJAX - Server Response97. AJAX XML Example98. AJAX PHP Example99. AJAX ASP Example100. AJAX Database Example101. XML Applications102. JavaScript JSON103. JSON Syntax104. JSON vs XML105. JSON Data Types106. JSON.parse()107. JSON.stringify()108. JSON Object Literals109. JSON Array Literals110. JSON PHP111. JSON HTML112. JSONP113. JavaScript / jQuery DOM Selectors114. JavaScript / jQuery HTML Elements115. JavaScript / jQuery CSS Styles116. JavaScript / jQuery HTML DOM117. JavaScript Graphics118. HTML Canvas119. Plotly.js120. Chart.js121. Google Chart122. D3.js123. JavaScript Interview Preparation

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HowTo Replace DateReplace new Date()Date ExampleReplace Date.now()Date ExampleTemporal ExampleReplace getFullYear(), getMonth(), getDate()Date ExampleTemporal ExampleReplace setDate() and Other Mutating MethodsReplace Date ArithmeticReplace Time Zone HandlingConvert Date to TemporalWhere to Replace Date with Temporal