How long for a ruptured tendon to heal by itself?

Most cannot heal: Most ruptured tendons pull apart and cannot heal because the ends are not close enough to heal. You should be evaluated by an orthopedic surgeon, who can tell you whether the tendon needs to be fixed or it will heal.

Tendon hand surgery: Lacerated or injured tendons or blunt injury is often called a rupture if the tendon is not in continuity, one sees the tendon fibrs are discontinuous and frequently neo tendon or psuedo tendon which s just scar forms in the onterval but it is weak and friable vs strong tendon tissue. While neo tendon may look like healing, it is not strong normal tendon tissue, but may b ok 4 partial injury

Won't: If it is completely "ruptured" the two ends will pull apart and it won't heal. It may scar down, but won't heal. If it is partially torn, then it can potentially heal over an 8-12 week period, but must be protected and followed closely.