Ask HN: anyone willing to contribute ideas for pricing for our startup?

Hi folks - we're coming out of beta soon and need to come up with pricing. trouble is I'm not sure how to price it. Is anyone willing to contribute ideas on pricing this service? Any input would be a help and much appreciated.

The service is an REST based API that converts documents to PDF and other formats, for example extracting text from documents.

The site is at http://www.pdfalchemy.com

I'm thinking that we should have subscription levels like:

$0 (free) per month to convert up to 100 documents per month

$x per month to convert up to 500 documents per month

$x per month to convert up to 1,500 documents per month

$x per month to convert up to 3,000 documents per month

$x per month to convert up to 10,000 documents per month

$x per month to convert up to more than 10,000 documents per month

I'd love some input from the HN community on what people think the prices per level should be, and also some input on the numbers of documents per month.

your input valued. thanks as