Certificate Transparency Log Lookup The Certificate Transparency Log Lookup queries public Certificate Transparency (CT) logs through the crt.sh aggregator to show every SSL/TLS certificate that has been issued for a domain. Enter a domain and instantly see which certificate authorities issued certificates, when they are valid, and which hostnames and subdomains they cover. Because the ...
Try the Tool »HSTS Preload Header Generator Build a correct Strict-Transport-Security header in seconds. Toggle max-age, includeSubDomains, and preload, then copy a ready-to-paste header value and matching server config. A live eligibility checklist tells you whether your header meets the rules for the browser preload list at hstspreload.org. How to Use Pick a max-age duration, or choose Custom ...
Try the Tool »CIDR Overlap / Subnet Conflict Checker Paste a list of CIDR ranges and instantly see which ones overlap. The checker performs exact bitwise comparison of every pair of subnets — for both IPv4 and IPv6 — and reports the precise conflicting address range and how many addresses collide. It is built for network engineers planning ...
Try the Tool »OAuth 2.0 Authorization URL Builder Assembling an OAuth 2.0 authorization request by hand is fiddly: every parameter has to be percent-encoded exactly, the PKCE code_challenge has to be a base64url-encoded SHA-256 hash of a random verifier, and the state and nonce values need to be unpredictable. Get one character wrong and the provider bounces you ...
Try the Tool »HAR to cURL Commands Extractor A HAR (HTTP Archive) file captures every network request your browser made on a page — but reading raw HAR JSON is painful, and reproducing a single request by hand is worse. This tool parses a HAR export entirely in your browser and turns each captured request into a ready-to-run ...
Try the Tool »DNS Propagation Checker When you change a DNS record — pointing a domain at a new server, swapping email providers, or rotating verification TXT entries — the update does not reach the rest of the internet at the same speed. Every recursive resolver caches answers for the length of the record’s TTL, so users on ...
Try the Tool »TLS/SSL Config Snippet Grader Paste an Apache or Nginx TLS/SSL configuration block and get an instant A–F grade based on Mozilla’s Server Side TLS guidelines. The grader flags deprecated protocols, weak ciphers, missing HSTS, and other security issues, then suggests a Mozilla-aligned replacement snippet you can drop straight into your server config. How to Use ...
Try the Tool »DNS Record TTL Expiry Calculator Plan DNS changes with confidence. Paste the records you just queried, set the moment they were fetched, and this calculator pinpoints the exact second every cached copy expires across resolvers — plus the safer “all-zones clear” propagation window for your migration. How to Use Paste one record per line in ...
Try the Tool »CSR (Certificate Signing Request) Generator Generate a PKCS#10 Certificate Signing Request and matching RSA private key entirely in your browser. Fill in the subject fields, add Subject Alternative Names, pick a key size, and click Generate. Both files are produced locally — the private key is never transmitted to any server, never logged, and never ...
Try the Tool »HAR to Postman Collection Converter Browser DevTools, Charles Proxy and mitmproxy all let you save captured traffic as a HAR (HTTP Archive) file, but Postman cannot import HAR directly. This converter rewrites a HAR export into a Postman Collection v2.1 JSON file in your browser, so you can replay every captured request as a real ...
Try the Tool »HAR File Performance Analyzer Upload or paste an HTTP Archive (HAR) file and instantly get a performance breakdown of every request the browser made: total transfer size, request count, slowest endpoints, biggest payloads, status code distribution and per-domain timing. Everything is parsed client-side in your browser — your HAR file never leaves the page. How ...
Try the Tool »Uptime / SLA Calculator Translate any service level agreement target into the precise downtime budget you are allowed across a year, quarter, month, week, day, or hour. The calculator works in three directions: convert an SLA percentage into allowed downtime, work backwards from a downtime ceiling to the SLA percentage you must commit to, and ...
Try the Tool »Web Vitals Score Calculator Plug in your LCP, INP, and CLS measurements and instantly see how your page rates against Google’s Core Web Vitals thresholds. The calculator returns a Good / Needs Improvement / Poor verdict per metric, a pass/fail summary for the page, and concrete fix suggestions for anything below target — all client-side, ...
Try the Tool »cURL to Code Converter Paste a curl command and instantly get the equivalent HTTP-client code in Python, JavaScript, PHP, Go, or Ruby. The converter runs entirely in your browser, parses curl with a real shell-aware tokenizer, and maps the flags you actually use — headers, JSON and form bodies, multipart uploads, basic auth, cookies, redirects, ...
Try the Tool »SWIFT/BIC Code Validator & Parser Paste any SWIFT or BIC code to validate its structure against the ISO 9362 specification and break it into its component parts. The tool checks character patterns, length, and identifies whether the code refers to a head office or a specific branch — all client-side, with no data ever leaving ...
Try the Tool »Network Speed Unit Converter Instantly convert between every common network and data transfer rate unit – bps, Kbps, Mbps, Gbps, Tbps, B/s, KB/s, MB/s, GB/s, TB/s, plus the binary IEC units like KiB/s and MiB/s. Type a value into any field and every other field updates live, so you never have to guess whether a ...
Try the Tool »Mock HTTP Response Builder Construct a structurally correct HTTP response message in seconds. Pick a status code, choose a body type, add headers, and the tool emits a ready-to-paste response string with the status line, headers, and body separated by CRLF — perfect for test fixtures, integration mocks, API documentation, and replaying responses against clients. ...
Try the Tool »Country Info Lookup Look up authoritative metadata for every country in the ISO 3166-1 standard — names, codes, dialing prefixes, currencies, capitals, and TLDs — in one place. The tool ships with a bundled dataset of 249 countries and dependent territories, so every search is instant, accurate, and works fully offline in your browser. Unlike ...
Try the Tool »Apache httpd Config Formatter Paste a messy Apache httpd.conf, apache2.conf, or sites-available/*.conf snippet and get back a properly indented, normalized configuration. The formatter walks <VirtualHost>, <Directory>, <Location>, <IfModule>, and other container tags to compute correct nesting depth, preserves your comments and blank lines, and can canonicalize directive case so that servername, SERVERNAME, and ServerName all ...
Try the Tool »Email Deliverability Checker Audit a domain’s email authentication setup in seconds. Enter any domain and the tool runs live DNS lookups against Cloudflare’s resolver to inspect SPF, DMARC, MX, and BIMI records, then surfaces real configuration problems with a clear pass/fail verdict and an overall deliverability score. How to Use Type the domain you want ...
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