Https://leakcheck.io/ - Payed, But you get passwords in clear text and there's a cheap 1 time payment option! Source: about 1 year ago

Sharing is caring, so I'll share one of mines. I tend to use google dorking as usual, but also use LeakCheck which is a rather handy tool to receive clear text passwords from Usernames, Email Addresses and such. Are there any other places, like these, that can be of use? :). Source: over 1 year ago

You could try https://leakcheck.net/ or https://www.dehashed.com/ (personally best for me) but they are paid unfortunately. Source: over 2 years ago

There was a data breach last year. Check on https://leakcheck.net/ whether your details were on there. Source: over 2 years ago

I think https://leakcheck.net/ might be the one you're looking for. For personal emails I use hacknotice.com. Source: about 3 years ago

You can check the DNS with whatismydns.net and intodns.com. Source: about 1 year ago

Feel free to check https://intodns.com/ and https://www.whatsmydns.net/ to monitor propagation and ensure the DNS records are correctly set. Source: about 1 year ago

Just in case, it would be a good idea to check the DNS with a tool like intodns.com, just to make sure everything is working as intended. Source: over 1 year ago

I know this is a little old but I came across some of my tools I used when going through bookmarks: - https://mail-tester.com Although I already mentioned this above, this has been a lifesaver when it comes to figuring out why 3rd parties are rejecting your mail - https://intodns.com Helps give you a more thorough view into how your DNS settings are configured. - https://mailu.io Not a diagnostic tool, but a... Source: over 1 year ago

If you need external confirmation of things, intodns.com and dnschecker.org are both pretty good. Source: over 1 year ago