Web Storage Limits

Internet Explorer "allows web applications to store nearly 10MB of user data. Chrome, Safari, Firefox, and Opera all allow for up to 5MB of user data, which is the amount suggested in the W3C spec.

Test Storage Exceed
A better approach to test to see if the quota is exceeded before saving important data. The way you test for this is by catching the QUOTA_EXCEEDED_ERR exception.

snippet
try {
sessionStorage["name"] = "Tabatha";
} catch (exception) {
if (exception == QUOTA_EXCEEDED_ERR) {
// we should tell the user their quota has been exceeded.
}
}
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