Accusoft was founded as Pegasus Imaging Corporation in 1991 as a reseller of fractal image compression and decompression toolkits and digital image compression applications. Pegasus Imaging was rapidly shifting from being a provider of end user utilities to marketing business-to-business solutions. A testament to the company's technology leadership, Accusoft is the only surviving commercial supplier of JPEG compression technology in the world. Well known photo imaging customers of Pegasus JPEG include Kodak, Canon, Nikon, Fujifilm, Konica Minolta and many others.

Accusoft is distinguished by its ability to deliver multiple interfaces to advanced technologies based on an extensive collection of intellectual capital, scientific research and product innovations. Today, the company holds a portfolio of 19 patents granted and a large amount of internal intellectual property (IP) related to imaging.

In early 1998, Pegasus Imaging Corporation was recognized as a Deloitte & Touche "Fast 500" company for its growth between 1993 and 1997. Around that time, the Pegasus Imaging acquired two companies for their successful product lines and technology. While business was good, the investment in systems integration was a detour from the original strategy of technology innovation. The investors recommended the integration division be spun off into a completely separate company. Pegasus Transtech was created and continues operations in Tampa, Florida.

During 1998, Pegasus expanded into the specialized medical imaging industry with the PICTools Medical software development kit containing a collection of image compression technologies ideal for medical images. PICTools Medical was quickly adopted by many of the largest medical technology companies in the world, including GE Healthcare, McKesson, Phillips Medical Systems, Siemens Medical Solutions and Toshiba.
In 2004, Pegasus Imaging acquired TMSSequoia. Their forms processing technology, document image cleanup technology and its employees, proved to be a valuable investment. The technology continues to be integrated into the Accusoft product portfolio.

On December 19, 2008 Pegasus Imaging acquired Accusoft, including the ImageGear product line. Accusoft’s powerful imaging products added significantly to Accusoft wide portfolio of imaging solutions.

Three weeks after the Accusoft acquisition was complete, Pegasus Imaging announced the acquisition of Tasman Software (Leeds, United Kingdom) and substantially all assets including its barcode software development kit (SDK) business. On January 9, 2009, Pegasus Imaging added Tasman’s Java and Java ME mobile barcode technology to its suite of document imaging products.

In 2009, Pegasus Imaging began doing business as Accusoft Pegasus. In October 2011, Accusoft Pegasus acquired Adeptol; further diversifying its product portfolio with the addition of the zero-footprint Adeptol AJAX Document Viewer, renamed Prizm Content Connect.

After 3 years as Accusoft Pegasus, the company rebranded to Accusoft in 2012. Today, Accusoft remains privately held, profitable and a wholly employee-owned corporation with headquarters located in Tampa, FL.