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Comparison

html.cloud vs emailing an .html file

html.cloud
Email attachment

Attaching an .html file to an email is the obvious move — and the one most likely to fail quietly. Mail providers treat HTML attachments as a phishing risk and often block or flag them, anything sizeable bounces on the attachment limit, and whatever gets through lives in inboxes and backups forever with no expiry. html.cloud sends a private, encrypted link instead — it opens as a page, and you can expire, replace, or delete it.

Why the attachment quietly fails

Because an HTML file can carry scripts, it's a textbook phishing vector, so Gmail and Outlook routinely strip .html attachments, drop them in spam, or slap a warning on them before the recipient can open — and none of that gives you a bounce message, so you often don't know it happened. If the file dodges the filters, it may still hit the ~25 MB attachment ceiling once it has embedded images or data. And the copy that does arrive is now permanent: it's in their inbox, your sent folder, and every backup, readable by anyone with mailbox access, with no way to pull it back or expire it. A link has none of those failure modes — html.cloud gives you one that opens the page directly, encrypted so only the people you send it to can read it.

At a glance

html.cloud.html email attachment
DeliveryA link that opens the page in the browserA file the recipient must download and open
DeliverabilityA normal link — nothing to stripOften blocked, quarantined, or flagged as risky
Size limitUp to 10 MB via the linkBounces past ~25 MB on most providers
PrivacyEncrypted in your browser; key only in the linkSits readable in inboxes, sent folders & backups
Expiry & revocation7 / 30 days / never; delete anytimeNone — once sent, it's out of your hands
Updating itReplace behind the same linkSend a whole new email

When emailing the file is genuinely fine

This isn't always the wrong choice. If the file is small, non-sensitive, and one-off — and you know the recipient's provider won't strip it and you don't care that it lives in their inbox forever — attaching it is simple and needs no third-party service at all. html.cloud earns its place the moment any of that stops being true: the file is confidential, it needs to render correctly when opened, it's too big to attach, or it might change after you send it. Then a link you control beats a file you've let go of.

FAQ

Why do HTML email attachments get blocked or flagged?

HTML files can contain scripts, so providers like Gmail and Outlook treat .html attachments as a phishing risk — stripping, quarantining, or warning before download. A link avoids that, and an html.cloud link opens the page directly in the browser.

Is there a size limit on email attachments?

Yes — Gmail caps attachments around 25 MB and others are similar, so a larger HTML file with embedded images bounces or gets auto-converted to a link. html.cloud delivers via a link from the start, up to 10 MB per file.

Can I expire or update a file after emailing it?

No — a sent attachment sits in inboxes and backups with no expiry or revocation, and changing it means a new email. With html.cloud you can expire it, delete it, or replace the file behind the same link so the recipient always sees the latest version.