Elliot Vance

Elliot Vance maintains Spark Zone. He builds and tests the calculators published here and writes the method notes that explain how each formula works. Every tool page writes out the calculation it applies, its input units and its default values; where a recognised standard or published rate table applies, the page names it. Reader-reported errors are checked against the calculation and logged by him, and a page is corrected when a rate, a standard or a reproduced error report requires it. Spark Zone is an independent reference site: not every tool has an external standard behind it, it is not affiliated with any professional body, and its calculators do not constitute financial, legal, or medical advice.