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Practical security knowledge for small business
Plain-English guides with sources, a glossary, and a free tool for every topic.
Security for small business
Website security
- How to Secure a Business WebsiteThe configuration and maintenance steps that matter most for small-business websites: HTTPS, updates, headers, cookies, admin access and monitoring.
- Website Security Headers ExplainedWhat each important HTTP security header does, the safe value to start with, and how to roll out Content-Security-Policy without breaking your site.
Email security
- How to Prevent Email Spoofing of Your DomainStep-by-step instructions to stop criminals sending email as your domain using SPF, DKIM and DMARC, with a safe path to enforcement.
- SPF vs DKIM vs DMARC: What Each DoesA plain-English comparison of SPF, DKIM and DMARC, how they work together, and which problems each one does and does not solve.
- DMARC Explained for Small BusinessesWhat DMARC is, what p=none, quarantine and reject mean, how reports work, and a safe plan to reach enforcement.
Domain security
Brand protection
- How to Detect a Fake Website Using Your BrandPractical ways to find lookalike domains and fake sites impersonating your business, and how to judge which ones matter.
- How to Respond to Business ImpersonationA calm step-by-step response plan: collect evidence, report to registrar and host, warn customers and prevent repeat incidents.
Glossary
DMARCSPFDKIMDNSSECTLSHTTPSContent-Security-Policy (CSP)HSTSSecurity headersMulti-factor authentication (MFA)PhishingDomain spoofingTyposquattingLookalike domainCAA recordsecurity.txtSubdomain takeoverSecure and HttpOnly cookiesData exposure
Free tools
Security CheckWebsite Security CheckerDomain Security CheckerEmail Security CheckerDMARC CheckerSPF CheckerDKIM CheckerSSL/TLS Certificate CheckerHTTPS CheckerSecurity Headers Checkersecurity.txt CheckerDNSSEC CheckerEmail Spoofing Risk CheckerWebsite Technology CheckerSecurity Score CheckerBrand Protection CheckerLookalike Domain Checker