Release of OAK Essentials

London, UK –  Operis, a leading adviser in project finance, today announces the launch of OAK Essentials, a new version of the Operis Analysis Kit, widely known as OAK, its long-established software for examining spreadsheets.

OAK is used by financial institutions around the world to develop and verify financial models that they really need to rely on. The new OAK Essentials makes available the four most popular functions which have made OAK one of the market leaders in Microsoft Excel Add-ins for spreadsheet modelling and review.

OAK Essentials can Summarize an Excel workbook, that is, list the worksheets, unique formulae and constants that make up a spreadsheet.  Going through this process is the natural first step in understanding a newly arrived, unfamiliar model.  Included in the resulting report is a risk analysis showing where among the formulae are concentrations of practices that are known to be error-prone.

With the Map tool, users can identify immediately the spreadsheet’s compliance with widely accepted best practices in financial modelling through a clear and understandable graphic representation.  These practices include left to right formula consistency and clear separation of inputs, calculations and outputs.

OAK’s Compare feature identifies what has changed between two versions of the same spreadsheet.  What is distinctive about OAK’s approach to this frequently performed task is its ability to align the spreadsheets being compared, so that the differences reported are true changes rather than spurious ones resulting from minor layout changes.

The Search functions identify spreadsheet cells that have undesirable characteristics, such as inclusion of hard-coded assumptions, containing values but not being referenced in any formula, or being the primary sources of errors that have propagated through a model.

OAK Essentials additionally introduces a News section with live updates on Operis financial modelling training courses, Operis blog posts and Excel tips and tricks.

OAK Essentials can handle Excel workbooks with up to ten worksheets. For an unlimited number of worksheets per workbook, an upgrade is available to the full version of OAK, now renamed OAK Professional.


OAK Essentials is available for £95.00 for a single license. For multiple licenses, upgrades to OAK Professional and OAK Professional licenses, please visit:

Contact Info

Rui Sobreiros

Product Manager