good marketing is built on details — and the checkers in this collection help you get those details right before they become problems. whether you’re auditing a technical seo element, reviewing your email copy for deliverability issues, or validating a sitemap, having a dedicated checker on hand makes the process faster and more reliable than doing it manually.
this collection includes tools for checking email spam trigger words, 301 redirects, subject line character counts, unsubscribe rate benchmarks, email preview text, xml sitemaps, canonical tags, title and meta description tags, anchor text, and keyword density. ten focused tools covering both email marketing and seo — the two disciplines where small technical oversights tend to have the biggest downstream impact.
all of them run in your browser, require no sign-up, and are free to use. bookmark the ones that fit your workflow and build them into your regular review process. catching issues early is almost always easier than fixing them after they’ve affected your results.