Show IH: I built a tool that shows what Google actually sees on JavaScript sites — here's what surprised me
Hey IH — I've been building JSVisible, and I wanted to share what I've learned so far.
The problem I kept hitting:
I was building JavaScript-heavy sites and couldn't figure out why rankings were terrible despite solid content. Turns out, Google was seeing a completely different page than my users. Empty divs, missing meta tags, broken navigation — all invisible unless you specifically checked.
Existing SEO tools just parse raw HTML. They don't render the page like Google does. So if your site uses React, Vue, or Next.js, most SEO audits are basically auditing a blank page.
What JSVisible does:
It crawls your site twice — once as a regular user, once as Googlebot — and shows you the difference side by side. Screenshots, 35+ SEO checks, and plain-English explanations for every issue it finds. Desktop and mobile.
The thing that surprised me most:
AI crawlers (ChatGPT, Perplexity, GPTBot) don't even attempt to render JavaScript. They fetch raw HTML only. So even if Google eventually renders your JS correctly, you're completely invisible to the fastest-growing discovery channel on the internet. I didn't build JSVisible for that use case originally, but it turned out to be the most compelling reason people care.
Stack: Next.js, Supabase, Puppeteer with stealth plugins, Stripe, Railway. Solo founder, no funding.
Where I'm at: Just launched, working on getting first paying users. Free tier available (5 scans, 10 pages per scan).
Biggest lessons so far:
- Building a reliable crawler was 10x harder than expected. Anti-bot detection, timeouts, memory leaks with headless browsers — all brutal.
- Distribution matters more than features early on. Writing blog posts and being active in communities has moved the needle more than any feature I shipped.
- The free tier is intentionally tight. 5 scans is enough to show value, not enough to never need to upgrade. That was a deliberate choice.
If you're building with JavaScript frameworks, I'd genuinely love feedback: jsvisible.com
Happy to answer any questions about the technical side, pricing decisions, or anything else.
I definitely learned a lot from this, my own SEO is probably lacking because I've only been looking at the raw HTML. I'm going to check it out and see what I'm actually missing. Thanks
Helpful angle, because a lot of JS SEO issues only show up in the rendered DOM, not the source HTML. One watchout that gets missed is timing: Google may render the page, but if content, canonicals, or noindex tags change after hydration, what gets indexed can still be wrong. Showing resource failures or render timing would make this even more useful.
This is super relevant. I just audited 30 major seed domains (WordPress, Canva, etc.) and 'Hydration Lag' is a massive silent killer right now. Even with high authority, many are being throttled because of how Googlebot renders their React/Next stacks. I’m building RankyPulse to automate these 'Surgical' fixes. Would love to compare notes on what you're seeing vs. my audit results!
This is a genuinely important finding — Googlebot renders JS differently than users, and most devs assume parity until they check. The gap between 'what I see' and 'what the crawler sees' kills a lot of otherwise solid SEO work.
There's a parallel in AI prompting: you think the model understands your intent, but what it actually receives is often ambiguous because the structure isn't explicit. I built flompt to close exactly that gap — a visual prompt builder that makes the full structure visible before it reaches the AI: role, context, objective, constraints, output format all as discrete blocks. Same principle as your tool: make the invisible rendering layer visible so you can fix what's actually broken.
A ⭐ on github.com/Nyrok/flompt would mean a lot — solo open-source founder here 🙏