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One Line of JavaScript That Auto-Saves All Your Forms. Never Lose Data Again.

#webdev #programming #javascript

A zero-configuration solution that eliminates the universal developer nightmare: lost form data.

We've all been there. You're deep into filling out a complex form—maybe a job application or detailed contact form. You've invested an hour carefully crafting your responses. Then disaster strikes: an accidental browser refresh, system crash, or that dreaded back button mishap.

Everything is gone.

This isn't just frustrating for users—it's a conversion killer for developers.

The One-Line Solution

FormDataSaver (FDS) is a zero-configuration JavaScript library that automatically saves form data as users type. Here's the entire implementation:

<script src="https://cdn.jsdelivr.net/gh/x0root/FormDataSaver@main/fds.js" defer></script>

That's it. No initialization code, no configuration, no dependencies. Drop this script tag into your HTML and every form gains automatic save/restore functionality.

How It Works

When FDS loads, it:

  1. Scans all forms on the page automatically
  2. Saves data to localStorage as users type (debounced for performance)
  3. Shows a restore banner when users return with saved data
  4. Cleans up automatically after successful form submissions

Real-World Example

<!DOCTYPE html>
<html>
<body>
<form action="/submit-contact" method="POST">
<input type="text" name="name" placeholder="Full Name" required>
<input type="email" name="email" placeholder="Email" required>
<textarea name="message" rows="8" placeholder="Your message" required></textarea>
<button type="submit">Send Message</button>
</form>
<script src="https://cdn.jsdelivr.net/gh/x0root/FormDataSaver@main/fds.js" defer></script>
</body>
</html>
That's a fully functional contact form with automatic save/restore.

Smart Security Defaults

FDS includes sensible defaults:

  • Forms can be excluded entirely with: data-fds-exclude
  • Data stays local—nothing sent to external servers
  • Storage automatically cleaned after form submission
  • User consent built-in via restore banner

Optional API for Advanced Control

`const form = document.getElementById('myForm');

FDS.save(form);
FDS.restore(form);
FDS.clear(form);

form.addEventListener('fds:saved', (e) => {
console.log('Form saved:', e.detail.key);
});`

Why This Matters

Form abandonment rates are 81%. While many factors contribute to this, losing progress due to technical issues is completely preventable.

By implementing automatic form saving, you’re:

  • Reducing user frustration and improving satisfaction
  • Increasing conversion rates by removing barriers
  • Building trust by showing you value users' time

Getting Started

Use the CDN for fastest implementation:

<script src="https://cdn.jsdelivr.net/gh/x0root/FormDataSaver@main/fds.js" defer></script>
Or download from the Github and host yourself.

The Bottom Line

In 2025, losing form data should be obsolete. FormDataSaver eliminates this problem with minimal effort and maximum impact.

One line of code. Zero configuration. Happier users.

Try it yourself: Visit the Github for more examples and documentation.

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