How to convert a date to ISO string in JavaScript
Łukasz Holeczek
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Converting dates to ISO string format is essential for API communication, data storage, and ensuring consistent date representation across different systems and timezones.
As the creator of CoreUI, a widely used open-source UI library, I’ve implemented ISO date formatting in countless API integrations over 25 years of development.
From my expertise, the most reliable approach is using the toISOString() method, which converts any Date object to the standard ISO 8601 format.
This ensures universal compatibility and precise timestamp representation.
Use toISOString() to convert Date objects to ISO 8601 format strings.
const date = new Date()
const isoString = date.toISOString()
// Returns: '2023-12-25T10:30:00.000Z'
Here toISOString() converts the Date object to a string in ISO 8601 format, which includes the full date, time, milliseconds, and ‘Z’ suffix indicating UTC timezone. This format is universally recognized and can be safely transmitted in APIs, stored in databases, or parsed by other systems regardless of their local timezone settings.
Best Practice Note:
This is the same date serialization approach we use in CoreUI components for consistent API communication. Always use ISO strings when sending dates to servers or storing them, as this format eliminates timezone ambiguity and ensures accurate date handling across different environments.
