xStorage Testing

This page will test your browser xStorage support.

Storage Type:

Value Length:

Max Values:

Random Key: Length:

Cycle: Count:

Use Four-byte Characters:

Clear Before:

Remove After:

Clear After:

Data:

These tests may take several minutes to run.
There may be periods when the tests seem frozen; they're not.
Your browser may pause the tests if the window becomes inactive.
A dialog will appear to inform you when the tests have completed.

These tests determine how many characters can be stored. Strings in JavaScript are UTF-16, so each character may require up to four bytes of memory. This means that while many browsers have a 5 MB limit, you may only be able to store ~2.5 M characters. Browsers are free to store the data on disk however they want, so measuring actual bytes isn't possible.