A standard shot glass typically holds about 44 milliliters (ml) in the United States, which is equivalent to 1.5 fluid ounces. However, the exact volume can vary depending on the country and the specific glass:

• United States: ~44 ml (1.5 fl oz)
• United Kingdom: ~25 ml or 35 ml (depending on the bar)
• Australia: ~30 ml
• Europe: Often around 20-30 ml

If you need a precise measurement for a recipe or drink, it's best to check the specific shot size used in your location.