The Type 4 Chi-To is the ultimate development of the line of medium tanks started with the Type 97 Chi-Ha. It is longer, wider, taller, better armed, and better armoured than the Type 97 Chi-Ha. The Type 4 Chi-To development started while the Type 97 Chi-Ha was still in production in 1943. The design specifications were simple: it required 75mm of front armour and a high-velocity 75mm gun. It was required to be able to face and beat the most current Allied tank of the time, the M4 Sherman.

The design included a new turret and hull, with the only commonality with the Type 97 being the drive-train, with the same bell crank suspen-sion, road-wheels, tracks, drive sprockets and return rollers. Everything else was new. It had an overall weight of about thirty tons.