Method for verifying the authenticity of a sensitive product, said sensitive product comprising an identifier comprising a set of characters, characterized in that the method comprises steps consisting in: - acquiring a test digital image comprising said identifier of said sensitive product; - optically recognizing characters of said identifier, - defining a set of distinctive points on the original digital image and on the test digital image of the sensitive product, a distinctive point being defined as a point of the digital image of the sensitive product, that is to say a pixel or a set of two-by-two adjacent pixels, for which the contrast gradient is greater than a predefined threshold value in at least one predefined direction and at a predefined distance around said set of at least one pixel, - extracting an optical fingerprint of the test digital image, - sending, to a remote server comprising a database comprising a set of original digital images of sensitive products, at least one from among: ∘ the optically recognized characters of the identifier, ∘ the optical fingerprint of the extracted test digital image, and ∘ said test digital image, - identifying, in the database, a set of at least one original digital image corresponding to said test digital image, - extracting an optical fingerprint of the corresponding original digital image, and - comparing the optical fingerprint of the test digital image and the optical fingerprint of the original digital image, wherein: - the step consisting in extracting an optical fingerprint of the test digital image is implemented in an identical manner to the step consisting in extracting an optical fingerprint of the original digital image, the extraction step (1000, 1120) comprising at least one of the steps from among: - a step of calculating local collisions, consisting in calculating, for at least one distinctive point, a set of local histograms in a determined subset of the digital image, said subset being part of the digital image which comprises said distinctive point, and - a metrology step consisting in calculating the distance between a first distinctive point and a second distinctive point on the original digital image or on the test digital image. - acquiring a test digital image comprising said identifier of said sensitive product; - optically recognizing characters of said identifier, - defining a set of distinctive points on the original digital image and on the test digital image of the sensitive product, a distinctive point being defined as a point of the digital image of the sensitive product, that is to say a pixel or a set of two-by-two adjacent pixels, for which the contrast gradient is greater than a predefined threshold value in at least one predefined direction and at a predefined distance around said set of at least one pixel, - extracting an optical fingerprint of the test digital image, - sending, to a remote server comprising a database comprising a set of original digital images of sensitive products, at least one from among: ∘ the optically recognized characters of the identifier, ∘ the optical fingerprint of the extracted test digital image, and ∘ said test digital image, ∘ the optically recognized characters of the identifier, ∘ the optical fingerprint of the extracted test digital image, and ∘ said test digital image, - identifying, in the database, a set of at least one original digital image corresponding to said test digital image, - extracting an optical fingerprint of the corresponding original digital image, and - comparing the optical fingerprint of the test digital image and the optical fingerprint of the original digital image, - the step consisting in extracting an optical fingerprint of the test digital image is implemented in an identical manner to the step consisting in extracting an optical fingerprint of the original digital image, - a step of calculating local collisions, consisting in calculating, for at least one distinctive point, a set of local histograms in a determined subset of the digital image, said subset being part of the digital image which comprises said distinctive point, and - a metrology step consisting in calculating the distance between a first distinctive point and a second distinctive point on the original digital image or on the test digital image.