Most kalimbas available for sale these days feature 17 tines. However, some models can have 7, 8, 9, 10, 12, or 15 keys. The difference between 15-tine and 17-tine models is not that significant, yet the extra keys make a great addition if you want to experiment more.
Beginners usually go for a 12-tine or 15-tine kalimba. Models that have fewer tines such as the ones with 7 or 8 keys are mainly used for relaxation and creating soothing sounds rather than for playing songs. If you’re interested in getting more creative and play various songs, then a kalimba sporting 15 or 17 keys is ideal.