Ten free tools for the technical side of search: generate Open Graph and schema markup, check heading structure, validate and build sitemaps, analyze links and image alt text, and measure readability. Everything runs in this page, in your browser — no sign-up, no server, nothing leaves your device.
Fill in your page details and get the full set of social meta tags, with a live preview of how the link will look when shared on Facebook and X (Twitter).
Tip: the preview image only loads if the image URL is public. Use an absolute URL (starting with https://) for the image — relative paths do not work in social meta tags.
Paste a page's HTML (or just its headings) and see the H1–H6 outline the way a search engine does — with skipped levels, missing H1s and over-long headings flagged.
Good structure: one H1 that states the page topic, H2s for main sections, H3s nested under them. Levels should step down one at a time — an H4 directly after an H2 usually means a level was skipped.
Paste a sitemap's XML to check it before search engines do: URL count, duplicates, broken or relative URLs, bad lastmod dates and protocol problems.
Limits that matter: a single sitemap file may hold at most 50,000 URLs and be at most 50 MB uncompressed. Bigger sites use a sitemap index pointing at several files.
Turn a plain list of page URLs — one per line — into a valid sitemap.xml with change frequency, priority and last-modified dates filled in.
Honest note: search engines largely ignore priority and change frequency — the value of a sitemap is the clean list of URLs itself. Invalid or duplicate lines are skipped and reported above.
Build the link tags that tell search engines which URL is the main version of a page, and which language or regional version to show each visitor.
Leave empty to use the page URL itself (a self-referencing canonical, which is the right choice for most pages).
The rule people break most: every version must list all the versions, including itself. If page A links to page B as its German version, page B must link back — otherwise search engines may ignore the whole set.
Choose how search engines may index a page and reuse its content in results and AI features, and get the exact meta robots tag — plus the X-Robots-Tag header version.
Careful: noindex removes a page from search results entirely once crawlers re-read it. It does not hide a page from visitors who have the link — that needs a password or login.
Structured data helps search engines understand a page and can unlock rich results — star ratings, FAQ dropdowns, breadcrumbs. Pick a type, fill the fields, and copy the finished script block.
Always true: markup must describe content that is actually visible on the page. Marking up reviews or FAQs that visitors cannot see can get the rich result removed — and the output above is only ever as honest as what you type in.
Paste your draft text to see how hard it is to read: Flesch Reading Ease, grade levels from five standard formulas, plus reading and speaking time.
What to aim for: most web copy lands well at a grade 6–9 level and a Flesch score of 60 or more — plain words, sentences under 20 words. Scores are guides, not grades: a technical page for specialists can be right at a higher level.
Paste a page's HTML to audit its links: internal versus external, followed versus nofollow, empty anchor text and the anchor texts a page leans on most.
| Anchor text | Destination | Type | Follow |
|---|
Reading the results: internal links spread a page's authority around your own site; external links point readers (and crawlers) elsewhere. Anchor text tells search engines what the destination page is about — a wall of "click here" wastes that signal.
Paste a page's HTML to find the images search engines and screen readers cannot understand: missing alt attributes, empty alt text, filenames pasted as alt text, and alt text long enough to be keyword stuffing.
| Image | Alt text | Status |
|---|
Empty alt is sometimes right: a purely decorative image should carry alt="" so screen readers skip it. What hurts is a missing alt attribute (no decision at all) and alt text that lists keywords instead of describing the picture.
SEOKit is a small workshop of ten SEO tools that run entirely in your browser. Paste, type, click — the work happens on your device, and nothing you enter is sent anywhere.
Every tool here was built for the checks site owners actually repeat: sharing tags before a launch, heading outlines before publishing, a sitemap sanity check before submitting it, alt text before a page ships. The tools are deliberately offline — view the page source and you can read every line of what they do.
Questions or a tool you wish existed? Write to hello [at] tapetoolhq.com.
Yes, free, and nothing is uploaded. Each tool is plain JavaScript running in this tab. There are no accounts, no quotas and no server-side processing — closing the tab deletes your inputs.
Browsers block pages from reading other sites' code (the same-origin rule), and SEOKit has no server to fetch with. Pasting the HTML — from View page source — gives the tools exactly the same material, privately.
No tool can promise that, and you should distrust any that does. What these tools do is remove avoidable technical mistakes — missing social tags, broken heading structure, invalid sitemaps, invisible images — so your content gets judged on its merits.
One sitemap file: at most 50,000 URLs and 50 MB uncompressed, URLs must be absolute and fully qualified. Larger sites use a sitemap index. The validator here checks each of those points.
No. Readability formulas measure sentence length and syllables, nothing more. A clear page usually serves readers better, and readers are the point — but a high score cannot rescue thin content, and a low one does not condemn a good technical page.
They solve different problems. A canonical picks the main version among duplicates; hreflang picks the right language or regional version per visitor. International sites usually need both, and the generator above builds them together so the sets stay consistent.