If the reading is very close or exact to the proper battery voltage, then the battery should still work. If it's not, then it's probably dead. Below is a list of the proper battery voltages as a guide: AA, AAA, C, and D alkaline batteries are 1.5 V.
Notice the voltage reading on the voltmeter. If the reading is more than 1.3V for alkaline battery (not rechargeable battery) then the battery still has some juice left in it, don't throw it away. Otherwise, properly discard of the battery. Tip : do not use old and new batteries in the same device at the same time.
We tested alkaline, lithium and zinc-chloride AA's to find the best AA batteries you can buy for. Best AA battery test results best value longest lasting high drain.