u51.top

u51.top is a disposable email domain

Trust score

0/100

Signals we found

  • Live website found +10
  • Registered to C20241024C_93299621-top +8
  • Linked social profiles found +5
  • Known disposable provider -60
  • High-abuse domain ending (.top) -15

Domain information

Registrar
NameSilo,LLC
Registered to
C20241024C_93299621-top
Registered
Oct 24, 2024 (1 year old)
A record
104.21.59.13
MX records
route3.mx.cloudflare.net (23)
route1.mx.cloudflare.net (68)
route2.mx.cloudflare.net (81)
Nameservers
emerie.ns.cloudflare.com
hal.ns.cloudflare.com
Authentication
SPF present · DMARC missing
Website
Sink - A Simple / Speedy / Secure Link Shortener with Analytics, 100% run on Cloudflare.
First seen
Jan 12, 2026

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Frequently Asked Questions

A disposable email domain provides temporary, throwaway addresses that expire or are abandoned shortly after use. People use them to sign up for something without handing over a real inbox, which is why they cluster around free trials, promotions and one-off downloads.
Yes. u51.top is classified as a disposable email domain in our database, based on the mail infrastructure behind it and the classification signals listed on this page.
They inflate signup numbers without producing users, distort activation and retention metrics, enable repeat free-trial abuse, and bounce later when the address expires — which damages your sender reputation.
Call the MailRook API from your signup form and check the address before you create the account. You get the same classification and trust score you see on this page, in a single request, and you can decide whether to allow, challenge or block.

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