In some examples, an ink level sensor includes a sense capacitor between a first node and ground, a first switch to couple a first voltage to the first node and charge the sense capacitor, a second switch to couple the first node with a second node and share the charge between the sense capacitor and a reference capacitor, causing a second voltage at the second node, and a transistor having a drain, a gate coupled to the second node, and a source coupled to ground, the transistor to provide a drain to source resistance in proportion to the second voltage.