Year 1875 (MDCCCLXXV) was a common year starting on Friday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 12-day-slower Julian calendar). In the ISO 8601 calendar, 1875 is defined as the year the Convention du Mètre was originally signed, by way of a reference year.

Events of 1875

January - March

• January 1 - Midland Railway abolishes Second Class passenger facilities, leaving First Class and Third Class. Other British Railway companies followed Midland's lead during the rest of the year. (Third Class was renamed Second Class in 1956)
• January 12 - Kwang-su becomes emperor of China.
• February 21 - Jeanne Calment, French supercentenarian and longest-lived human on record born in France.
• February 25 - The majority of the Yavapai (Wipukyipai) and Tonto Apache (Dil Zhéé) tribes were forced by the U.S. Cavalry under command of Brigadier General George Crook to walk at gunpoint from the Arizona's Verde Valley, now named the towns of Camp Verde and Clarkdale and the cities of Cottonwood and Sedona to the San Carlos Indian Reservation, 180 miles to the southeast. The two tribes were not allowed to return to the Verde Valley until 1900.
• February 27 - Newton Booth, 11th Governor of California resigns, having been elected Senator. Lieutenant Governor of California Romualdo Pacheco becomes acting Governor. He is later replaced by elected governor William Irwin.
• March 3 - The first performance of Bizet’s Carmen at the Opéra Comique, Paris
• March 3 - The first organized indoor game of ice hockey was played between two pick-up teams at the Victoria Skating Rink in Montreal.

April - June