xolotl doesn't come with a automatic unit handling system like in NEURON, BRIAN, or in Julia, so you have to pay attention and make sure your parameters are in the right units. The following are default units for various parameters.

Variable	Units
Length of compartment	mm
Surface area of compartment	$mm^2$
Volume of compartment	$mm^3$
Voltage	mV
Specific capacitance of membrane	$nF/mm^2$
Specific conductance of channel	$μS/mm^2$
Synaptic strength	nS
Current injected into cell	nA
Axial resistivity	MΩ mm
Calcium concentration	μM
temperature	K