Free diagnostic tools for small business
Know exactly what's healthy in your business tech, and what isn't.
Free checks for your domain, email authentication, and security hygiene, the stuff that quietly breaks when no one is watching. No signup, no jargon, just a clear verdict and the next step.
The tools
Pick a tool and run a free check
MX Lookup
See which servers handle your domain's email, with a verdict for each.
SPF Check
Find out if your domain is letting email impersonators through.
DMARC Check
See what happens to email that tries to impersonate your domain.
DKIM Check
Confirm your outgoing email is cryptographically signed and verifiable.
DNS Lookup
Check A, AAAA, MX, TXT, NS, and CNAME records for any domain.
Blacklist Check
See if your domain or mail server is on an email blacklist.
WHOIS Lookup
See who registered a domain, when it expires, and whether it's protected.
Why these tools
The depth a sysadmin expects, in language anyone can act on
Plain-English verdicts
Every result opens with a clear pass, warning, or fail, not a wall of raw records.
A clear next step
You don't just get data. Each check tells you whether to act and exactly what to do next.
Industry-grade data
Each tool matches the data depth of the paid utilities sysadmins reach for, then translates it.
From the blog
Practical technology decisions for small teams
Why Outlook Keeps Asking for Your Password (and How to Stop It)
Repeated Outlook password prompts are almost always caused by stale saved credentials or an outdated sign-in method — both fixable in minutes.
Read note
What to Do When an Employee Leaves: An IT Offboarding Checklist
Block the account and revoke sessions first, within minutes, not days. Everything else follows in order. Here's the full checklist for Microsoft 365 and Google Workspace.
Read note
How to Recognize and Respond to a Phishing Attack
The first 60 minutes after a suspected phishing click matter most. Block the account, revoke sessions, change the password, in that order.
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