From Side Project to 10,000+ Monthly Users: My Lessons from Building a Dev Tool Solo
Hi š
Iām Anil, a front-end dev from India. A few months ago, I launched FormatJSONOnline ā a simple, privacy-first tool to format, validate, and convert JSON data, all in the browser.
Today, the site is averaging 10,000+ monthly users organically without any paid marketing.
Hereās what Iāve learned building this tool solo while juggling client work and life.
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š Why I Built It
Like most devs, I constantly work with JSON ā API responses, logs, configs, etc. I used several online formatters but found them either:
- Too slow
- Full of ads/popups
- Or not secure (sending data to the server)
So I built my own:
- Fully client-side (no data is ever sent)
- Fast and clean UI
- Free and ad-free (for now)
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š My Stack
- Frontend: Next.js + Tailwind CSS
- Hosting: Vercel
- Analytics: Simple Analytics
- SEO: Manual + programmatic meta tags
- No backend: 100% static
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š Growth Highlights
- š First 100 users: Reddit + Dev.to + IndieHackers
- š Added to niche directories: Product Hunt, Daily.dev, StackShare, etc.
- š SEO took ~6 weeks to kick in
- š Word of mouth + long-tail keywords helped
- š§Ŗ Now experimenting with blog content & JSON-related tools
> ā Currently seeing ~10,000 users/month and growing
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š§ Features That Helped
These small additions made a big difference:
- [JSON to Excel]ā Great for devs working with Excel
- [JSON Filter]ā Like jq, but in-browser
- [JSON Compare] ā For debugging APIs
- [Copy as cURL] ā For developers who need to transfer data to and from a server quickly via terminal
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š” Lessons Learned
1. Simple tools can win if you focus on UX and speed
2. SEO is slow but powerful ā write helpful titles and descriptions
3. Niche communities work ā Reddit, Dev.to, IndieHackers brought early traction
4. Build first, monetize later ā ads coming soon, but value first
5. You donāt need a backend to ship something useful
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š Whatās Next
- Add more JSON utilities (search, merge, API support)
- Start monetization via ethical ads
- Grow blog traffic through helpful content clusters
- Maybe open-source part of the tool
---
š Over to You
If youāve built a developer tool or a small utility site:
- How did you get your first users?
- Any monetization tips before enabling ads?
You can try my tool here: Format JSON Online
Would love your feedback!
Also happy to answer any questions about building small SaaS-like tools solo š
Great..
Thank you
Congratulations on reaching this milestone, Anil.
I'm also building a free utility tool. Not for developers, though.
I have the same concern in mind:
"How did you get your first users?"
"Any monetization tips before enabling ads?"
My questions:
I see you've built multiple small tools on your website. Do you think "tool as marketing" can perform better than "content marketing"?
In my opinion, there are several json formatters on the internet. Do you think if a tool is really niche and unique, it can draw more traffic?
Thanks for sharing! I'm currently at a phase when I have already a product aimed for devs and power users with a few licenses sold and I'm looking at how to scale it through SEO. I used some of the links you provided - that was really helpful! Good luck with your product!
This is super inspiring, Anil! Love how you identified a common developer pain and solved it with a clean, privacy-first approach. The fact that you hit 10k+ monthly users organically is a strong sign that you're solving a real problem ā and doing it well.
Your lessons around SEO, UX focus, and niche communities really resonate. Itās also motivating to see that you managed all this without a backend or paid marketing. Massive respect
Iām just getting started with building small tools myself ā curious to know, how do you prioritize which feature to add next when you're solo?
Keep going! Subscribed and bookmarked your tool
Love this, Anil ā the simplicity, speed, and client-side privacy-first angle is spot on. I totally agree that small, high-utility tools can quietly rack up serious usage, especially with dev-focused audiences.
Iām building CompliAssistant, an AI-powered HIPAA compliance assistant for small teams. JSON and structured data are everywhere in compliance too ā e.g., audit logs, risk registers, access controls ā so lightweight tools like yours are a huge help.
Curious: have you had any inbound interest from teams using it for regulated industries (e.g., healthcare, finance, etc.)? Might be an interesting niche to explore for monetization.
Thanks for sharing the transparent breakdown ā super insightful š„