The exact requirements vary by type of airspace, whether it is day or night (for countries that permit night VFR), and from country to country. Typical visibility requirements vary from one statute mile to five statute miles (many countries define these in metric units as 1,500m to 8km). Typical cloud clearance requirements vary from merely remaining clear of clouds to remaining at least one mile away (1,500m in some countries) from clouds horizontally and one thousand feet away from clouds vertically. For instance, in Australia, VMC minima outside controlled airspace are clear of cloud with 5,000m visibility below 3,000ft AMSL or 1,000ft AGL (whichever is higher), and 1,000ft vertical/1,500m horizontal separation from cloud above these altitudes or in controlled airspace. Above 10,000ft, 8,000m visibility is required to maintain VMC. Air Traffic Control may also issue a Special VFR clearance to VFR aircraft, to allow departure from a control zone in less than VMC - this reduces the visibility minimum to 3,000m.
Generally, VMC requires greater visibility and cloud clearance in controlled airspace than in uncontrolled airspace. In uncontrolled airspace there is less risk of a VFR aircraft colliding with an IFR aircraft emerging from a cloud, so aircraft are permitted to fly closer to clouds. An exception to this rule is class B airspace class, in which ATC separates VFR traffic from other VFR traffic and from IFR traffic, which is why in Class B Airspace lower cloud clearance is required.