[Crawl-Date: 2026-03-09]
[Source: DataJelly Visibility Layer]
[URL: https://datajelly.com/blog/free-seo-tools-we-use-every-day]
# Free SEO Tools We Use Every Day | Blog | DataJelly
> A walkthrough of the free diagnostic tools we built and use daily — with real workflows showing how to diagnose a site's visibility problems in under 60 seconds.

---

We built these tools because we needed them ourselves. Every day we use them to diagnose client sites, test new features, and validate that DataJelly is doing its job. They're all free, they all run in the browser, and they don't require an account.

Here's how we actually use them — not a feature list, but real workflows that help us diagnose a site's visibility problems in under 60 seconds.

## The Toolkit at a Glance

We currently maintain 15 free SEO tools, organized into four categories:

- **Audit & Testing** — Visibility Test, Site Audit, Bot Test, SEO Diagnostic Quiz, Site Crawler
- **Validators** — Robots.txt Tester, Sitemap Validator, Structured Data Validator, SSL Checker
- **Analyzers** — Metadata Viewer, Page Speed Analyzer, HTTP Header Checker, HTTP Status Checker
- **Infrastructure** — DNS Records Viewer, Website Screenshot

You can explore all of them at [/seo-tools](https://datajelly.com/seo-tools) . Below, we'll walk through three real use cases.

## Use Case 1: "Is my site even visible?"

This is where most people start. You've built a React SPA, shipped it to production, and you want to know: can Google actually see my content?

Open the [Visibility Test](https://datajelly.com/seo-tools/visibility-test) , enter your URL, and hit run. You'll get a side-by-side comparison showing what a human sees versus what a bot sees when it visits the same page.

What to look for:

- **Big gap?** Your JavaScript isn't being rendered for bots. Prerendering will fix this.
- **Small gap?** Most of your content is visible, but some dynamic sections might be missing.
- **No gap?** You're in good shape — bots see what humans see.

This single test tells you whether you have a visibility problem. It takes about 10 seconds and answers the most important question first.

## Use Case 2: "Why does my shared link look blank?"

You share your site on Slack or LinkedIn and the preview card is empty — no title, no image, no description. This is one of the most common complaints we hear from teams shipping JavaScript-heavy apps.

**Step 1:** Open the [Social Card Preview](https://datajelly.com/seo-tools/social-card-preview) and enter the URL. Check whether your Open Graph tags (`og:title`, `og:image`, `og:description`) are present in the raw HTML response.

**Step 2:** Run the [Bot Test](https://datajelly.com/seo-tools/bot-test) on the same URL. This shows you what a specific crawler (Googlebot, GPTBot, etc.) actually receives. If the meta tags are rendered client-side only, social bots won't see them — they don't execute JavaScript.
**The fix:** Your OG meta tags need to be present in the initial HTML response — either through server-side rendering, static generation, or prerendering. If you're using React Helmet or a similar library, the tags are only injected after JavaScript runs, which is too late for social bots.

## Use Case 3: "My site is slow and I don't know why"

Performance issues often aren't in your code — they're in your infrastructure. We use two tools together to narrow this down quickly.

**First:** Run the [Page Speed Analyzer](https://datajelly.com/seo-tools/page-speed-analyzer) to get your Core Web Vitals — LCP, FID, CLS. This gives you the user-facing symptoms: is the page slow to load, slow to interact with, or visually unstable?

**Then:** Use the [HTTP Header Checker](https://datajelly.com/seo-tools/http-header-checker) to inspect the response headers. Check for:

- **Cache-Control** — Is the browser caching your assets? No caching means every visit is a full re-download.
- **Content-Encoding** — Is gzip or brotli compression enabled? Uncompressed responses can be 5–10x larger.
- **Server timing** — Some hosts add timing headers that reveal backend bottlenecks.

Often, enabling caching and compression at the hosting level cuts load time in half — no code changes required.

## The 60-Second Diagnostic

If you only have a minute and want a quick health check, here's the sequence we run:
1. [Visibility Test](https://datajelly.com/seo-tools/visibility-test) — Can bots see your content?
2. [Structured Data Validator](https://datajelly.com/seo-tools/structured-data-validator) — Is your schema markup valid?
3. [Sitemap Validator](https://datajelly.com/seo-tools/sitemap-validator) — Is your sitemap well-formed and accessible?
4. [SSL Checker](https://datajelly.com/seo-tools/ssl-checker) — Is your certificate valid and properly configured?
Four tools, under a minute. If all four pass, your fundamentals are solid. If any fail, you know exactly where to dig deeper.

## What's Next

We're continuously expanding the toolkit. Recent additions include the [HTTP Bot Comparison test](https://datajelly.com/seo-tools/bot-test) (see exactly what different crawlers receive) and the [SEO Diagnostic Quiz](https://datajelly.com/seo-tools/seo-diagnostic) (an interactive walkthrough that recommends the right tools for your situation).

Every tool is free, runs in the browser, and requires no signup. If there's a diagnostic you wish existed, [let us know](https://datajelly.com/contact) — we build what we need, and we're always looking for the next gap to fill.

Explore the full suite: [datajelly.com/seo-tools →](https://datajelly.com/seo-tools)

— Jeff
Founder, DataJelly

## Page Metadata
- Canonical: https://datajelly.com/blog/free-seo-tools-we-use-every-day
- OG Title: DataJelly - The Visibility Layer for Modern Apps
- OG Description: Rich social previews for Slack & Twitter. AI-readable content for ChatGPT & Perplexity. Zero-code setup.
- OG Image: https://datajelly.com/datajelly-og-image.png
- Twitter Card: summary_large_image
- Twitter Image: https://datajelly.com/datajelly-og-image.png

## Structured Data (JSON-LD)
```json
{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What free SEO tools can I use to check if my site is visible to search engines?","acceptedAnswer":{"@type":"Answer","text":"DataJelly\u0027s free Visibility Test shows a side-by-side comparison of what humans see versus what bots see when visiting your URL. It takes about 10 seconds and immediately reveals whether your JavaScript-rendered content is accessible to search engine crawlers."}},{"@type":"Question","name":"Why does my shared link preview look blank on Slack or LinkedIn?","acceptedAnswer":{"@type":"Answer","text":"Blank link previews happen when your Open Graph meta tags (og:title, og:image, og:description) are only rendered client-side by JavaScript. Social bots like FacebookExternalHit and LinkedInBot don\u0027t execute JavaScript \u2014 they need the tags present in the initial HTML response. Use the Metadata Viewer to check if tags are present, then the Bot Test to confirm what crawlers actually receive."}},{"@type":"Question","name":"How can I diagnose why my website is slow?","acceptedAnswer":{"@type":"Answer","text":"Use the Page Speed Analyzer to get your Core Web Vitals (LCP, FID, CLS), then the HTTP Header Checker to inspect caching and compression headers. Often, enabling Cache-Control headers and gzip/brotli compression at the hosting level cuts load time in half without any code changes."}},{"@type":"Question","name":"What is the fastest way to run an SEO health check on my site?","acceptedAnswer":{"@type":"Answer","text":"Run four free tools in sequence: 1) Visibility Test to check bot rendering, 2) Structured Data Validator to verify schema markup, 3) Sitemap Validator to confirm your sitemap is well-formed, 4) SSL Checker to verify your certificate. This 60-second diagnostic covers the fundamentals."}},{"@type":"Question","name":"How many free SEO tools does DataJelly offer?","acceptedAnswer":{"@type":"Answer","text":"DataJelly maintains 15 free SEO tools organized into four categories: Audit \u0026 Testing (Visibility Test, Site Audit, Bot Test, SEO Diagnostic, Site Crawler), Validators (Robots.txt Tester, Sitemap Validator, Structured Data Validator, SSL Checker), Analyzers (Metadata Viewer, Page Speed Analyzer, HTTP Header Checker, HTTP Status Checker), and Infrastructure (DNS Records Viewer, Website Screenshot). All run in the browser with no signup required."}},{"@type":"Question","name":"Do I need an account to use DataJelly\u0027s SEO tools?","acceptedAnswer":{"@type":"Answer","text":"No. All 15 SEO tools are free, run directly in your browser, and require no account or signup. You can start diagnosing your site immediately at datajelly.com/seo-tools."}}]}
```


## Discovery & Navigation
> Semantic links for AI agent traversal.

* [Features](https://datajelly.com/#features)
* [Pricing](https://datajelly.com/pricing)
* [Visibility Test](https://datajelly.com/visibility-test)
* [Prerendering](https://datajelly.com/prerendering)
* [Lovable SEO](https://datajelly.com/lovable-seo)
* [Visibility Layer Guide](https://datajelly.com/guides/visibility-layer)
* [How Snapshots Work](https://datajelly.com/guides/how-snapshots-work)
* [AI SEO Platform](https://datajelly.com/ai-seo-platform)
* [Bot Detection](https://datajelly.com/bot-detection)
* [Dashboard](https://dashboard.datajelly.com/)
* [SEO Tools](https://datajelly.com/seo-tools)
* [Visibility Test](https://datajelly.com/seo-tools/visibility-test)
* [Site Audit](https://datajelly.com/seo-tools/site-audit)
* [Bot Test](https://datajelly.com/seo-tools/bot-test)
* [Social Card Preview](https://datajelly.com/seo-tools/social-card-preview)
* [Robots.txt Tester](https://datajelly.com/seo-tools/robots-txt-tester)
* [Sitemap Validator](https://datajelly.com/seo-tools/sitemap-validator)
* [Structured Data Validator](https://datajelly.com/seo-tools/structured-data-validator)
* [HTTP Header Checker](https://datajelly.com/seo-tools/http-header-checker)
* [Page Speed Analyzer](https://datajelly.com/seo-tools/page-speed-analyzer)
* [SSL Certificate Checker](https://datajelly.com/seo-tools/ssl-checker)
* [DNS Records Viewer](https://datajelly.com/seo-tools/dns-records-viewer)
* [Guides](https://datajelly.com/guides)
* [Getting Started](https://datajelly.com/guides/getting-started)
* [SPA SEO Guide](https://datajelly.com/guides/spa-seo)
* [JavaScript SEO Guide](https://datajelly.com/guides/javascript-seo)
* [SSR Guide](https://datajelly.com/guides/ssr)
* [Search Engine Crawling Guide](https://datajelly.com/guides/search-engine-crawling)
* [Lovable SEO Guide](https://datajelly.com/guides/lovable-seo)
* [AI SEO Testing Guide](https://datajelly.com/guides/ai-seo)
* [SEO Testing Guide](https://datajelly.com/guides/seo-testing)
* [SERP Tracking Guide](https://datajelly.com/guides/serp-tracking)
* [Security Testing Guide](https://datajelly.com/security)
* [About Us](https://datajelly.com/about)
* [Contact](https://datajelly.com/contact)
* [Blog](https://datajelly.com/blog)
* [Terms of Service](https://datajelly.com/terms)
* [Privacy Policy](https://datajelly.com/privacy)