A.B. Addo
Malmö, Sweden

The company was founded by the Swedish dentist Hugo Agrell in 1918. In 1966 the company was bought by by Facit. The full-keyboard calculators had the name Addo and the 10-keyboard calculators Addo-X. A subsidiary of Addo was Dixma (see Dixi).

Swedish company. Addo has been making mechanical adding machines from approximately 1920 and also electro-mechanical adding machines already in the thirties Later it also made rotary calculators. The company originally produced full keyboard mechanical calculators and they called all their ten key mechanical adders (the first of them about 1936) Addo-X. X here means the roman numeral ten. Thus it should be consistent to call Addo pocket calculators also Addo-X.

Addo and Facit did fuse about 1968.

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