This research introduces a compact, auto-aligning interferometer engineered for measuring translations with a wide angular working range and picometer precision above 1Hz. It presents a design ensuring automatic beam alignment during movement through secondary reflection from a corner reflector. The sensor head, a 20×10×10mm 3 all-glass quasi-monolithic structure, exhibits a displacement sensitivity below 1pm/Hz 1/2 above 1Hz and a wide angular working range of ±200mrad. This versatile optical design holds promise to improve the sensitivity in applications such as laser ranging, optical seismometers, precision manufacturing, and metrology.