What is the LR44 equivalent?

LR44 battery equivalent and size

LR44: 1.5 V alkaline button cell, 11.6 mm × 5.4 mm, about 120 mAh (180 mWh). Same battery: AG13, A76, L1154, 1166A, PX76A. Also fits: SR44.

1.5 Vvoltage

11.6 mmdiameter, 0.46 in

5.4 mmthick, 0.213 in

≈ 120 mAhcapacity

LR44 to scale. Alkaline manganese dioxide, not rechargeable.

AG13, A76, L1154, 1166A and PX76A are all the same alkaline LR44 cell; the SR44 (357 / 303) is the silver oxide version of the same size.
Bulk packs of LR44s are cheap but uneven in quality. For calipers, watches and light meters, the silver oxide SR44 keeps a steady voltage to the end.
LR44 and CR2032 are often confused because both power small electronics, but they differ in size (11.6 mm button vs 20 mm coin) and voltage (1.5 V vs 3 V).

AG13A76L11541166APX76A

Battery	Size	Volts	Works?	Why
SR44	11.6 mm × 5.4 mm	1.55 V	Yes	Same size; silver oxide lasts longer (an upgrade).
SR1136SW	11.6 mm × 3.6 mm	1.55 V	Short-term	1.8 mm thinner: may sit loose; fine short-term.
LR43	11.6 mm × 4.2 mm	1.5 V	Short-term	1.2 mm thinner: may sit loose; fine short-term.
SR43	11.6 mm × 4.2 mm	1.55 V	Short-term	1.2 mm thinner: may sit loose; fine short-term.
Size 675	11.6 mm × 5.4 mm	1.45 V	No	Zinc-air cells need air holes; not for sealed devices.
CR2032	20 mm × 3.2 mm	3 V	No	Wrong voltage: 3 V vs 1.5 V.
CR1/3N	11.6 mm × 10.8 mm	3 V	No	Wrong voltage: 3 V vs 1.5 V.

Two LR44s stacked = 3 V, 10.8 mm: the same as one CR1/3N, which lasts longer.

Silver oxide version: SR44, about 170 mAh vs 120 mAh, steadier voltage: better for watches, calipers and thermometers.