What Causes React Hydration Errors and How to Understand Them

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Hydration errors occur in server-side rendered web applications when the HTML generated by the server does not match what the client-side JavaScript framework expects to find in the browser. The hydration process is the step where client-side JavaScript attaches itself to pre-rendered server HTML to make a page interactive. A common cause is dynamic content such as dates and times, which may render differently depending on the server's timezone versus the user's local timezone. Another frequent trigger is the use of browser-specific APIs like the window or document objects during server-side rendering, where such APIs do not exist. Understanding these mismatches helps developers build more stable SSR applications using frameworks like React, Vue, or Angular.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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