Wellington business consultant Tony Ryburn is making life easier for DIY share investors with a new online portfolio management tool designed to automatically calculate true returns and produce all data for taxation requirements.

Mr Ryburn said the system, Sharesight, was developed mainly for people who bought online and whose shares were not placed with traditional brokers.

"I had been messing around with shares and wanted to manage my own portfolio but found preparing for tax returns and the accounts of my family trust was a time-consuming nuisance," he said.