In general, you do not need photo ID to board a Greyhound bus in the United States. However, if photo ID is required, a Mexican passport is valid for that purpose.
A passport photo should be 2 inches by 2 inches in size for official documentation.
pass
Passport booklet size are approximately 3.5 inch (Width) x 5.0 inch (Height).
To apply for a Mexican passport, you will need the following documents: a birth certificate, a valid photo ID, proof of Mexican citizenship, a completed application form, and two passport-sized photos.
That is 'passport' size. It may,however, depend on the country from which you get the passport to travel to Saudi Arabia.
It varies from place to place. In India 3.5 x 3 is the size for a passport photo.
Load picture - make sure it not a backround In Edit > Transform > scale and change the size to that of a passport photo
UK are 3.5cm width and 4.5 cm length
6x4 (cm)
Passports must have a photo of only the individual applying for the passport. These are wallet sized photos and can be taken at any photo processing center.
To apply for a Mexican passport, you will need to provide a completed application form, proof of Mexican citizenship, a valid photo ID, a recent passport-sized photo, and payment for the application fee. Additional requirements may vary depending on your specific circumstances, so it is recommended to check with the Mexican consulate or embassy for the most up-to-date information.