8 Free SEO Tools We Built for Webmasters and Web Designers

We've been hosting websites since 2002. In that time, we've answered thousands of support tickets about SSL errors, DNS misconfigurations, broken meta tags, and mystery ranking drops. The same issues come up over and over, and the fixes are usually quick once you can see the problem.

So we built eight free tools that solve the most common technical headaches webmasters face. No sign-up, no paywall, no usage limits. Just type a URL or domain and get answers. Here's what each one does, why it matters, and how it can save you time.

HTTP Header Inspector

Your server sends HTTP headers with every page request. They control caching, security policies, content types, and redirect behaviour. But most site owners never see them, and misconfigured headers cause problems that are hard to diagnose without the right tool.

The HTTP Header Inspector fetches the full response header chain for any URL. It follows redirects so you can see every hop, grades your security headers from A to F, and flags what's missing. If your Content-Security-Policy is absent or your X-Frame-Options header isn't set, you'll know in seconds. We cover the full grading system and how to fix each header in our deep-dive on HTTP security headers.

Can I check my website's security headers for free? Yes. The 365i HTTP Header Inspector scans any URL and grades security headers from A to F, showing which headers are missing and what each one protects against. No sign-up required.

DNS Lookup Tool

DNS is the phone book of the internet, and a wrong entry means your site, email, or subdomains stop working. Around 17% of email delivery failures trace back to DNS misconfigurations, things like missing MX records or broken SPF syntax. And with only 18% of domains having proper DMARC policies in place, most businesses are exposed to spoofing attacks without realising it.

Our DNS Lookup Tool queries every record type (A, AAAA, MX, TXT, NS, CNAME, SOA, CAA, SRV) via Cloudflare's DNS-over-HTTPS resolver. It doesn't just list records. It checks your email authentication health: SPF, DKIM, and DMARC get individual status cards showing pass, warning, or fail states.

How do I check if my domain's DNS is configured correctly? Enter your domain into the 365i DNS Lookup Tool. It queries all record types and grades your email authentication (SPF, DKIM, DMARC) with clear pass/warning/fail indicators.

Why No Padlock? (Mixed Content Scanner)

You've installed an SSL certificate, but the padlock icon is missing. Usually that means something on the page (an image, a script, a font) is still loading over plain HTTP. Browsers block or downgrade these "mixed content" resources, and your visitors see security warnings instead of the padlock. With 86.9% of the web now using HTTPS, a missing padlock stands out.

The Why No Padlock? scanner crawls any HTTPS page and identifies every insecure resource. It grades your overall security from A+ to F, shows SSL/TLS certificate details, and lists each mixed content item with its source URL so you can fix it.

Why is my SSL padlock not showing? Mixed content: one or more resources on your page are loading over HTTP instead of HTTPS. The 365i mixed content scanner finds every insecure resource and tells you exactly which file on which line to fix.

Meta Tag Checker and SERP Preview

Roughly 25% of top-ranking pages have missing or poorly written meta descriptions. That's traffic left on the table. Your title tag and meta description are your search result advert, and if they're truncated, duplicated, or absent, click-through rates suffer. Open Graph tags matter too: 22.2% of websites use no structured sharing data at all, meaning social previews look broken or pull the wrong image.

The Meta Tag Checker extracts every meta tag from any URL and shows you a live Google SERP preview, plus Facebook and Twitter card previews. It flags SEO issues (missing canonical, no viewport tag, title too long) with severity indicators. You see exactly what search engines and social platforms see. Our deep dive into the Meta Tag Checker covers common mistakes and how title tags affect your Google Discover visibility.

How can I preview how my page looks in Google search results? The 365i Meta Tag Checker generates a pixel-accurate SERP preview from your actual meta tags, plus Facebook and Twitter previews. It flags truncation, missing tags, and SEO issues.

"Technical SEO is not going away. A lot of it is not a matter of blind trust or hope. It's something that's very deterministic, and you can logically find the answer."

John Mueller, Search Advocate at Google, via Search Engine Journal

Mueller's point is why we built these tools. We host sites for hundreds of UK businesses. The pattern we see is always the same: excellent content held back by a technical problem the owner didn't know existed. A missing security header. A DNS record that's slightly wrong. A robots.txt file accidentally blocking Googlebot. These are five-minute fixes once you can see them, but invisible without the right diagnostic tools.

Robots.txt Checker

Your robots.txt file tells search engine crawlers which parts of your site to access and which to skip. Get it wrong and you could block Googlebot from your most important pages. One misplaced wildcard in a disallow rule can accidentally hide your entire site from search results, and you'd have no idea until rankings drop.

The Robots.txt Checker fetches and parses any site's robots.txt, breaking down rules by user-agent. You can test specific URL paths against the rules to see if they'd be allowed or blocked. It spots common mistakes: overly broad disallow patterns, missing sitemap references, and conflicting rules that AI crawlers might interpret differently from Googlebot.

How do I test if my robots.txt is blocking Google? Paste your domain into the 365i Robots.txt Checker. It parses every rule, lets you test specific URLs against the crawl directives, and flags mistakes that could accidentally block search engines. We go deeper into why robots.txt checking matters for AI crawlers in the full tool guide.

WHOIS Lookup

Domain registration data tells you who owns a domain, when it expires, which registrar manages it, and what nameservers are configured. This matters for due diligence on domain purchases, checking competitor domains, or simply making sure your own registration isn't about to lapse.

Our WHOIS Lookup uses RDAP (the modern replacement for the legacy WHOIS protocol) to pull registration details, dates, nameservers, domain status codes, registrar info, and DNSSEC status. Results are grouped into clear sections so you can quickly find what you need. If your domain is approaching expiry, you'll see it immediately.

How do I check when a domain name expires? Enter the domain into the 365i WHOIS Lookup. It shows the exact registration date, expiry date, last updated date, nameservers, and registrar via the RDAP protocol.

Post Sitemap to CSV

Content audits start with knowing what pages a site has. Manually copying URLs from XML sitemaps is tedious and error-prone, especially for sites with thousands of pages. And if the site uses a CDN that blocks automated requests (Akamai, Cloudflare Bot Management), most sitemap tools just fail silently.

The Post Sitemap to CSV tool discovers all XML sitemaps for any website, fetches page titles in progressive batches (starting with 1, ramping up to 5 at a time), and exports everything as a clean CSV. If a CDN blocks the proxy request, it offers a paste-XML fallback so you can still extract the data. Results are cached for 30 days, so repeat visits are instant.

How do I export a website's sitemap URLs to a spreadsheet? Use the 365i Post Sitemap to CSV tool. Enter a domain, it discovers all XML sitemaps automatically, fetches page titles for each URL, and lets you download a clean CSV file. We cover five practical workflows for your exported CSV (content audits, redirect mapping, competitor research, and more) in our deeper guide to sitemap exporting.

Why a Hosting Company Builds Free Tools

It's a fair question. We sell WordPress hosting, managed cloud servers, and security services. Why give away tools for free?

"Setting up a Search Console account helps you monitor and optimise how your website performs on Google Search."

Google Search Central, SEO Starter Guide

Google's own advice is that site owners should use diagnostic tools to understand their sites better. We agree. Running a hosting company for over two decades has taught us that the best customer is an informed one. When a client understands their DNS, knows their SSL is working, and can check their meta tags, they spend less time confused and more time growing their business. For web designers and freelancers managing multiple client sites, these tools pair well with fixed-cost agency hosting where every site gets its own staging and management panel. And when they need hosting that matches the standards these tools measure against, they know where to find us.

Every tool runs on our own performance-optimised edge infrastructure, built for speed and reliability. They're the same diagnostic checks our support team runs daily. We just put a browser interface on them and made them public.

Frequently Asked Questions