I recently went looking for an API to do some text conversions ( markup->html) I found OUTRAGEOUS prices. The lowest entry was cloudconvert at $9 a month for 1000 roughly conversions. I can't give the exact number because they have a complicated credit system, and some conversions cost more than others. ConvertAPI has a 1000 conversion tier, at $30 a month. It's ridiculous. So I built t3xtr, it's a clean simple API with 100 free conversions a month. You can get a plan for as low as $6 that gives you 5000 per month. It can convert Markdown ↔ HTML, HTML → PDF, PDF → Text, JSON ↔ YAML, CSV ↔ JSON, and Text cleaning/normalization.

It's a custom nodejs server using plugins and it's nothing you couldn't do at home, but it's fast, it's easy, and it's free.