All Tools View Categories About Contact Privacy

TLS Strength Checker

Score pasted TLS config against protocol and cipher best practices.

Runs entirely in your browser - nothing is uploaded and no cloud connection is made.
Your TLS strength report will appear here.
-
score
-
grade

About TLS Strength Checker

A TLS server block can look correct and still negotiate weak protocols or non-forward-secret ciphers, and those failures are invisible until an audit or a breach. Reading ssl_protocols, ssl_ciphers, session ticket and stapling settings by eye is error-prone. The TLS Strength Checker parses the configuration you paste with the built-in nginx tokenizer, scores it against protocol and cipher best practices, and reports a 0-100 grade while making no live connection to any server.

At the heart of the configuration are a handful of directives. ssl_protocols should list only TLSv1.2 and TLSv1.3 and never any SSL or early TLS version. ssl_ciphers should begin with ECDHE suites to guarantee forward secrecy. ssl_prefer_server_ciphers off lets the client pick among equal-strength modern suites. ssl_session_tickets off avoids shared-ticket weaknesses that undermine forward secrecy. ssl_stapling on attaches a signed OCSP response for faster, private revocation checks. add_header (Strict-Transport-Security) enforces HTTPS and is part of a complete TLS posture. Together they shape how the server behaves, and the tool assembles them in the right context so the result is valid on the first try.

Common mistakes are easy to make. Accidentally leaving SSLv3 or TLSv1 in ssl_protocols re-enables broken protocols. Using only AES-CBC or non-ECDHE suites removes forward secrecy from the handshake. Leaving session tickets on with static keys quietly weakens forward secrecy. Forgetting OCSP stapling makes clients contact the CA and slows the handshake. The generator anticipates each of these and either sets a safe default or rejects the input with a clear message before anything is written to your clipboard.

Validation is strict because small configuration errors fail in subtle ways. Every input is checked for plausibility, and after the block is assembled it is re-parsed by a built-in tokenizer so unbalanced braces, missing semicolons or stray characters cannot reach your clipboard. Stat cards report line and block counts, and copy, download and print exports are one click away. Everything runs in your browser; nothing you type is transmitted to any server.

In practice this block drops into any standard nginx install. Save the output as a file under /etc/nginx/conf.d/ (or sites-available with a symlink), run nginx -t to confirm the syntax, then reload with nginx -s reload. Because the generator emits a single, self-contained server block with no hidden dependencies, it composes cleanly with your existing caching, logging and security configuration without directive collisions.

Beyond producing correct config, the tool is a reference you can read back and learn from. Each control maps to a real nginx directive, the sample button shows a complete working block in seconds, and clearing the form resets every field to its safe default. Standardising on a generator like this removes per-developer variation, keeps your configuration readable, and gives you a repeatable, auditable setup that passes nginx -t on the first try.

When something looks wrong in production, the first move is always to re-run nginx -t and inspect /var/log/nginx/error.log; most failures surface there with a line number. The access log records every request, so a sudden spike or a wall of 499 responses points straight at backend or timeout problems the generator helps you avoid in the first place.

This server block is designed to sit alongside - not fight - your other configuration. Because it declares its own server_name and a single, self-contained set of directives, you can drop it into conf.d without worrying about collisions with global caching, logging or security snippets that live elsewhere in the nginx tree.

For a production site, pair this block with TLS termination: serve on 80 for the redirect or health checks, and place the encrypted listener (or a front-end load balancer / CDN) in front so clients always speak HTTPS. The generator keeps that boundary clean so the two layers compose instead of overlapping.

If a change ever needs to be undone, the output is plain text you control: delete the file from conf.d, re-run nginx -t, and reload. There is no database and no hidden state, so rolling back is as simple as restoring the previous version from version control or your own backup.

Performance and correctness both benefit from explicit configuration. Defaults baked into the generator reflect current best practice rather than decades-old forum snippets, so the block you ship today will not surprise you with deprecated directives or insecure fallbacks six months from now.

For teams, a generated block is also documentation. New engineers can read the exact directives in place, compare them against the sample, and learn the relevant nginx behaviour without reverse-engineering a hand-maintained file that drifted from its original intent.

Finally, because every value is validated before it is written, the risk of a typo taking down the whole server is low. A malformed domain, a missing path, or an impossible port is caught up front with a message you can act on, instead of a silent failure at reload time.

Features

  • ssl_protocols - should list only TLSv1.2 and TLSv1.3 and never any SSL or early TLS version.
  • ssl_ciphers - should begin with ECDHE suites to guarantee forward secrecy.
  • ssl_prefer_server_ciphers - off lets the client pick among equal-strength modern suites.
  • ssl_session_tickets - off avoids shared-ticket weaknesses that undermine forward secrecy.
  • ssl_stapling - on attaches a signed OCSP response for faster, private revocation checks.
  • add_header (Strict-Transport-Security) - enforces HTTPS and is part of a complete TLS posture.
  • Self-verifying output re-parsed before display.
  • Copy, Download and Print exports.
  • Load-sample button fills realistic values.
  • Statistics cards for quick checks.
  • Runs entirely in your browser - nothing uploaded.

How to Use

  1. Open the TLS server block from your nginx config.
  2. Copy the ssl_* directives and paste them into the text area.
  3. Click Score TLS config (or Load sample).
  4. Read the per-check PASS/FAIL lines.
  5. Note the overall Score and Grade.
  6. Fix the failing checks in your real config.
  7. Re-paste and re-score until you reach grade A.

Examples

Example 1 - Strong config modern protocols, ECDHE, tickets off, stapling on scores 100.

Example 2 - Deprecated protocols SSLv3 and TLSv1 present fails the protocol check.

Example 3 - No ECDHE AES256-SHA only fails the forward-secret cipher check.

Example 4 - Parse error an unbalanced brace is reported as a parse error, not a score.

Example 5 - Missing HSTS a valid TLS block without HSTS still loses a point.

Benefits

  • Parses real nginx syntax before scoring.
  • Fixed protocol and cipher best-practice checklist.
  • Clear 0-100 score and letter grade.
  • Points directly at the failing directive.
  • JSON export for compliance tracking.
  • Private: everything runs in your browser.

Frequently Asked Questions

Does this connect to a server?
No. It only scores the TLS configuration text you paste; no handshake is attempted.
What makes a protocol deprecated?
SSLv2, SSLv3, TLSv1 and TLSv1.1 are broken or weak and should never appear in ssl_protocols.
Why require ECDHE ciphers?
ECDHE provides forward secrecy so captured traffic cannot be decrypted later even if the key leaks.
Why disable session tickets?
Shared ticket keys can undermine forward secrecy; disabling them (or rotating keys) is the safer default.
What does OCSP stapling do?
It lets the server attach a signed revocation response so clients avoid contacting the CA directly.
Is HSTS part of TLS strength?
It is the policy layer that enforces HTTPS, so the checker rewards its presence in the server block.
Can I export the result?
Yes - copy, download or print the report, and use the JSON button for a machine-readable summary.
Is anything uploaded?
No. The configuration you paste stays in your browser.