Free tools for software & saas

JWT Decoder Decode JWT headers and payloads, see expiry in plain English and verify HMAC signatures without pasting tokens into a third-party server. UUID Generator Generate UUID v4 or time-ordered v7 IDs in bulk, and validate any UUID you are debugging. Unix Timestamp Converter Convert Unix timestamps in seconds, milliseconds or microseconds, with Europe/London time and BST handled correctly. Base64 Encode & Decode Encode and decode Base64 and data URIs, including UTF-8 text and files, with a URL-safe option for tokens. SPF Record Checker Check whether your SPF record stays under ten DNS lookups as you add a CRM, helpdesk and billing tool. A PermError means receivers treat SPF as failed, which can push sig... DKIM Record Checker Confirm each sending service signs with a valid DKIM key on your domain. When you switch transactional email provider, check the new selector before cutting over so passw... DMARC Record Checker Review your DMARC policy and reporting address. Moving from p=none to quarantine and then reject protects customers from phishing emails that pretend to be your billing t... SPF Record Generator Rebuild a clean SPF record when the existing one has grown messy. List only the services that genuinely send as your domain, and move high-volume senders to subdomains wh... Email Header Analyzer Paste the headers of a signup email that landed in spam. It shows which authentication checks passed or failed and which servers handled the message, which speeds up supp... Security Headers Checker Check the marketing site and app login page for HSTS, CSP and framing protection. Having good results ready makes security questionnaires quicker to answer honestly. TLS Version Checker Confirm the app and API endpoints no longer accept TLS 1.0 or 1.1. Buyers and auditors often ask about this directly. AI Crawler Checker See whether GPTBot, ClaudeBot, PerplexityBot and Google-Extended are allowed or blocked. Many SaaS teams want AI search visibility for the marketing site while keeping ap... Schema Markup Validator Validate SoftwareApplication, Organization and FAQ structured data on product and pricing pages so search engines understand what the product is and who makes it. XML Sitemap Checker Check that the marketing and docs sitemaps list only canonical, indexable URLs, and that they do not leak app routes or staging paths. Image Compressor Product screenshots exported from design tools are often large PNGs. Converting them to WebP in the browser keeps feature pages fast without uploading unreleased UI anywh... Compress PDF Reduce the size of scanned or image-heavy sales decks and case study PDFs before emailing them, so they clear attachment limits. Text becomes part of the image, so keep a... SSL Certificate Checker See whether a site's TLS certificate is valid, who issued it, and how many days it has left — before your visitors see a browser warning Website Down Checker Find out in seconds whether a website is down for everyone or only on your connection, and what kind of failure it is Keyword Grouping Tool Paste a keyword list or upload a CSV export, and group it into topics you can plan one page around, with intent buckets and summed volume, impressions and clicks Bulk Redirect Checker Paste or upload up to 100 URLs and see where each one really ends: every hop with its status code, chains, loops and temporary redirects, plus a match check against the t... Email Verifier Check whether an email address looks deliverable before you send: format, typos, mail servers, disposable and role addresses, one at a time or 50 at once XML to JSON Converter Turn RSS feeds, sitemaps, SOAP responses and other XML into clean JSON, or build XML from JSON, with full control over how attributes, arrays and namespaces are mapped Privacy Policy Generator Answer five short questions about your business, the data you collect and the tools you use, and get a starting-point privacy policy you can review, edit and publish WHOIS Lookup See the full public registration record for any domain: registrar and abuse contact, key dates, every status code in plain English, nameservers, DNSSEC and the raw record SSL Certificate & CSR Decoder Paste a PEM certificate, a full chain or a CSR to read every field in plain English, check that each certificate signs the next, and catch problems before you install it Subnet Calculator Enter any IPv4 or IPv6 address with a prefix or mask to get its network, host range, masks, address type and reverse DNS zone, then split it, plan VLSM subnets or summari... HTTP Headers & Compression Checker Enter a URL to see every response header it sends, whether gzip or Brotli compression is on and how much it saves, and what its caching headers tell browsers and CDNs llms.txt Checker & Generator Enter a website to validate its llms Website Technology Checker Enter any website to find out which CMS, builder or store platform it runs on, the scripts and services it loads, and who hosts its website, DNS and email, with the evide... MTA-STS, TLS-RPT & BIMI Checker Enter a domain to validate its MTA-STS record and policy file, confirm the policy lists every mail server, check TLS-RPT reporting, and see whether BIMI is set up and all... Subdomain Finder Enter a domain to list the subdomains recorded in public Certificate Transparency logs, check which ones still resolve, and flag forgotten records that could be taken ove...