Lumin PDF, founded in 2014, has 60 million users across the world, with 20m people signing up just this year.
PDF, or Portable Document Format (developed by Adobe in the 1990s), is a file format to present a document in the exact way it is intended to be read, and one of the widest used document formats.
Lumin said it has seen a 600 percent growth in sales during 2021, and customers include companies like Blockchain, Netflix and Uber.
Its 29-year-old founder and chief executive Max Ferguson is eyeing up further growth, hoping to reach $10m in sales soon, and to double its user number.
Lumin is also the world's largest Google Cloud PDF software partner and easily integrated with the Google eco-system, he said.
That meant people who liked Google products such as Gmail, liked Lumin, he said.
"Lumin PDF has a philosophy of making software as easy as possible, easy to get started and easy to get used. I think now there's a lot of different PDF options on the market but people really resonate with that message," Ferguson said.
"There has been a huge uptake and a lot of movement from more sort of traditional softwares that are hard to use, over to Lumin which is easy to use."
Ferguson, originally from the West Coast, started Lumin after completing his degree in Civil Engineering at the University of Canterbury, and then working in the Christchurch rebuild.
"I saw first-hand the significant amount of documentation that was being used and signed manually, just in the construction industry alone.
"I thought there has to be a better way and it inspired my initial idea for Lumin."
Ferguson said he was open to options in order to take the company further, to the point where it would make an impact on a large number of people.
"I think in order for us to drive the maximum value, there will become a point where a merge, either us acquiring other companies or a merger with another company, or allow us to bring more value to the customers."
Ferguson said the Lumin had also decided it would keep Christchurch as its main base of operations.
