Duo Two-Factor Authentication vs Really Simple SSL
Compare WordPress plugins and tools side by side. Pick products with “Compare” in the software directory.
| Feature | Duo Two-Factor Authentication v2.5.7 · checked 23 Oct 2026 Free · ★ 3.7/5 Visit Details | Really Simple SSL v9.8.3 · checked 23 Oct 2026 Free + paid · ★ 4.9/5 Visit Details |
|---|---|---|
| At a glance | ||
| Active installs | 3,000+ | 3M+ |
| Last updated | June 6, 2025 | September 15, 2026 |
| Editions | Duo Two-Factor Authentication | Really Simple Security · Really Simple Security Pro ($) |
| Pros | Two-factor login by role, set in the plugin settings; Uses the Duo Security service and its verification methods; Free plugin with no paid edition in the code | One-click HTTPS migration with 301 redirects; Hardening options such as XML-RPC and user enumeration; Email two-factor login for chosen roles in the free version |
| Cons | Needs a Duo account with integration and secret keys; No firewall, lockout, malware scan or activity log | Captcha, authenticator 2FA, passkeys and firewall need Pro; Vulnerability checks send plugin and theme names to a remote service; Many settings screens to review after setup |
| Mentioned in our posts | 1 | 1 |
| Features (Security plugins checklist) | ||
| Firewall | No | Paid |
| Malware scan | No | No |
| Login protection | No | Yes |
| Two-factor login | Yes | Yes |
| Activity log | No | No |
| Free version | Yes | Yes |
| More features | ||
| Other features | Two-factor login required by role, Duo Web iframe prompt at login, XML-RPC disabled unless allowed, Network admin options on multisite | One-click HTTPS migration and redirects, Vulnerability detection for plugins, themes and core, Email two-factor login for roles, WordPress hardening options, Authenticator app two-factor login ($), Captcha on login (reCAPTCHA or hCaptcha) ($) |
| Integrations | ||
| Marketing | — | Really Simple Security mailing list |
| Other | Duo Security | Cloudways API, SSL Labs, Really Simple Security vulnerability service, Google reCAPTCHA ($), hCaptcha ($) |
| Requires WordPress | 4.1 | 6.6 |
| Requires PHP | — | 7.4 |
| Tested up to | 6.0 | 7.1 |
| Phones home | No | No |
| External services | — | api.cloudways.com, api.ssllabs.com |