Methods and apparatus to certify digital signatures are disclosed. An example method includes retrieving, from a first database, a first geographical location associated with an identification number associated with a network device and identified in a request to certify a digital signature, comparing the first geographical location associated with the identification number to a second geographical location to verify the second geographical location, determining that the first geographical location matches the second geographical location, and certifying the digital signature to indicate an authenticity of the digital signature based on the verification of the second geographical location and a comparison of (a) biometric information associated with a user associated with the request and (b) stored biometric information.