Hey! Hope you're doing well.
So, I spent way too much time last night debugging a weird routing issue in a React app, and stumbled on this tool State-in-URL that actually saved my ass. You know how single-page apps shove all sorts of state into the URL—filters, pagination, modal states—and it becomes this unreadable mess of encoded JSON? I had a bug where deep linking wasn't restoring the UI correctly, and manually decoding the URL parameters in the console was driving me insane.
What I tried first (and why it failed miserably)
Opened the browser console, copied the URL, pasted it into a decoder website. Did that about fifteen times, each time getting more frustrated. The state was nested JSON, base64-encoded, then URL-encoded—basically impossible to read. I was spending more time decoding than actually fixing the bug.
What I eventually figured out
State-in-URL has this real-time monitoring feature where you connect it to your browser tab, and it automatically parses the entire URL state into an editable tree view. No copy-paste, no manual decoding. It showed me immediately that the issue was a deeply nested property that was being dropped during serialization because of a typo in the key name. Would've taken me hours to spot that manually.
I found this page with the system requirements that mentioned the browser extension: the resource I used. Wait, that's not right—let me find the correct one. Actually, the official State-in-URL documentation has all the details, and Apple's Safari Developer Tools guide helped me understand what's built into the browser versus what this tool adds.
What actually helped (the stuff I wish I'd done first)
- Used the diffing tool. I saved two states—one working, one broken—and let the app compare them. Highlighted the exact difference in red. Instant answer.
- Checked the browser extension. There's a Safari extension that adds a "View in State-in-URL" button right in the toolbar. One click and you're analyzing.
- Realized the encoding/decoding panel lets you test transformations live. I could see what the decoded JSON looked like before and after each encoding step, which made the pipeline finally click.
The app also flagged that our URL was dangerously close to the browser length limit (we were storing entire filter sets in there). It suggested using a hash-based approach instead, which we're now migrating to.
A couple of other things I stumbled on
- The state presets feature is great for QA. You can save a particular URL state (like "user logged in, filter active, modal open") and reload it instantly for testing.
- It integrates with testing frameworks—you can export a state as a Jest test case. Haven't tried it yet but looks promising.
- The tool warned about "over-serialization" where we were storing derived data in the URL instead of just the raw parameters. Cleaned that up and the URL length dropped by 40%.
I also found this article on URL encoding best practices from MDN—not directly related to the tool, but helpful background.
Checklist for next time (so I don't repeat mistakes)
- Keep the browser extension installed—it's faster than launching the app separately.
- Use diffing immediately when comparing working vs broken states.
- Check the warnings panel—it catches subtle issues like encoding mismatches or near-length limits.
- Save interesting states as presets before tearing down your dev environment. Future you will thank you.
Anyway, if you ever find yourself staring at a URL like https://site.com/?state=eyJmaWx0ZXIiOnsic2VhcmNoIjoiZm9vIn19 and wanting to scream, grab this thing. Let me know if you try it—curious if it handles your stack's encoding as smoothly.