Why I Built My Own File Conversion API (And You Probably Shouldn't)

The Problem That Started It All
I needed to convert some Markdown to HTML for a client project. Simple, right? Just find an API, make a few calls, move on with life.
Narrator: It was not simple.
The Great API Price Hunt of 2025
Here's what I found:

ConvertAPI: $30/month for 1,000 conversions
CloudConvert: $8/month for ~500-1000 conversions (depends on processing time)
Others: Even more expensive or terrible quality

Wait, what?
For context, converting Markdown to HTML is basically running a few regex operations and a parser. This should cost pennies, not dollars.
The "I Could Build This" Moment
Every developer has had this thought. Usually, we're wrong. The existing solution handles edge cases we haven't considered, has enterprise features we need, or took years to perfect.
But sometimes... sometimes the emperor really has no clothes.
What I Actually Built
Tech Stack:

Node.js + Express
PostgreSQL for user management
PM2 for process management
Vanilla JS frontend (I dislike frameworks ok?)

Conversions Supported:

Markdown ↔ HTML
HTML → PDF
PDF → Text
JSON ↔ YAML
CSV ↔ JSON
Text cleaning & normalization

The entire backend is maybe 6-700 lines of actual conversion logic, and tons of plugins I configured. The rest is authentication, rate limiting, billing integration, and error handling.

My pricing:

100 free conversions/month
$6 for 5,000 conversions
$11 for 10,000 conversions
$20 for 20,000 conversions

That's roughly $0.0012 per conversion vs the industry's $0.03.
What I Learned

1. Sometimes when you say to yourself " I could do this better" You are right.
2. A lot about securing a service, this is my first SaaS project, but hardly my first JS one.
3. Sometimes things cost way more than they need to, this is running on a small vps, but if people use it I will upgrade to keep performance great. The overhead is pretty minimal. Time sink: This was supposed to be a weekend project. It's been weeks. Support burden: Users expect enterprise reliability at indie prices Market risk: Competitors could drop prices tomorrow Opportunity cost: Could have built something more innovative

But sometimes it's worth it if:

The pricing gap is truly absurd (25x counts)
You can execute significantly faster/cheaper
You enjoy the technical challenge
You see a real path to sustainability

The Results So Far
Live for a day. Users signing up.Product Hunt pending.
More importantly: I learned that sometimes the "impossible" competitive landscape just needs someone willing to charge reasonable prices.
Try It Out
If you need file conversion and don't want to pay enterprise prices for simple operations: t3xtr.org
100 free conversions to test it out. No credit card required.