newbie here so please pardon me if I'm asking a silly question.
Currently I am required to work with Lat/Long coordinates in WGS84 (EPSG:4326) on QGIS for data analysis.
The input data I have comes in NZ Topo 50 Grid References and I need to transform this into WGS84 Lat/Long coordinates. The tool that I have used to do this successfully previously was the detailed online converter from LINZ found here: http://apps.linz.govt.nz/coordinate-conversion/index.aspx?Advanced=1
However, the online converter only takes in 6 figure grid references (e.g. BA32 123456) whereas I need to convert a more granular 10 figure grid reference (e.g. BA32 123.45 678.91).
Other software from LINZ that I have tried are NZMapConv and Concord. However, NzMapConv only allows up to 8 figure grid references for NZ Topo50 and does not allow bulk conversions whereas Concord does not even contain NZ Topo50 as an option (despite having support for bulk conversions).
As such, are there any tools, software, code that I may have missed that would allow me to easily do bulk conversions from NZ Topo 50 10 figure Grid References into Lat/Long coordinates for WGS84? I'm also open to trying to script my own solution but I was unable to find the algorithm or mathematical formula for the conversion.