A travel adaptor can make a plug fit a socket without changing the voltage or frequency supplied to the device. Electrical Safety First's adaptor guidance makes that distinction explicit. Fitting the socket and being suitable for the electricity supply are different questions.
For VoltRoute, I included origin and destination in the inputs together with the device's input range, frequency and type, and kept voltage, frequency and plug conditions separate in the result. Choosing a destination alone would leave out the equipment someone intended to take.
Bringing the device into the comparison
The input range describes the voltage a device or its power supply is designed to accept. Two devices taken to the same place can have different input ranges. The design therefore takes the country's supply information and the device's input requirements separately before comparing them.
Frequency concerns the repeating cycle of an alternating-current supply; the plug is the physical connection to the socket. A voltage comparison and a plug-fit check use different information, so I kept their results separate. I wanted someone reading the result to understand what had been compared and where to turn to the device label or manufacturer guidance for the remaining details.
Following the comparison back to its sources
I placed sources and review dates beside the results, together with a warning that an adaptor does not change voltage. A number on its own does not make clear whether it describes a country's general supply or a requirement of a particular device. The source gives the reader a route back to the information and its scope.
That route is especially important when country information has exceptions or a device's input label is unreadable: it leaves the label and manufacturer instructions as checks to make before choosing an adaptor. I also organised a monthly update plan for maintaining the information. Sources and review dates provide a basis for deciding which material to revisit and when.
Conditions to check before connecting equipment
Voltage, frequency and plug shape are only part of the comparison: earthing requirements and the adaptor's rating also matter. Electrical Safety First warns that some adaptors are unsuitable for equipment requiring an earth connection and that their maximum rating must not be exceeded. High-power or heat-producing equipment, frequency-sensitive devices such as motors or clocks, and unreadable input labels call for manufacturer or qualified professional guidance.
VoltRoute's result does not replace electrical certification or a manufacturer's confirmation. My work here was to organise the information to compare before connecting a device and provide a way to check it. That is why I separated country and device conditions and kept the route back to their sources visible.