It depends entirely on your glass size. A 250ml glass gives exactly 4 glasses per litre. A 200ml glass gives 5. Select your glass size below and get instant answers — glasses to litres or litres to glasses.
There is no officially standardised "glass" measurement — it varies by country and context. In the UK, a standard drinking glass is typically 250ml. In the US, a cup is 240ml (8 fl oz). Australian glasses often range from 200–250ml. Use the calculator above with your actual glass size for the most accurate result.
The maths is simple: 1000ml ÷ glass size (ml) = glasses per litre. For a 250ml glass: 1000 ÷ 250 = 4 glasses. For a 200ml glass: 1000 ÷ 200 = 5 glasses. For a 300ml glass: 1000 ÷ 300 = 3.33 glasses. Use the calculator above to skip the arithmetic entirely — just type your amount and get instant answers.
Health guidelines typically recommend 2 litres (2000ml) per day for adults. Using a 250ml glass, that's exactly 8 glasses. With a 200ml glass, you'd need 10 glasses. With a 300ml glass, roughly 6.67 glasses. The daily goal varies by weight, climate and activity — but 2 litres / 8 glasses is the most common starting point.
Use this table to find how many glasses are in any amount of water, or how many litres are in any number of glasses — for the four most common glass sizes.
| Litres | ml | 150ml glass | 200ml glass | 250ml glass | 300ml glass |
|---|---|---|---|---|---|
| 0.25 L | 250 ml | 1.67 glasses | 1.25 glasses | 1 glass | 0.83 glasses |
| 0.5 L | 500 ml | 3.33 glasses | 2.5 glasses | 2 glasses | 1.67 glasses |
| 0.75 L | 750 ml | 5 glasses | 3.75 glasses | 3 glasses | 2.5 glasses |
| 1 L | 1000 ml | 6.67 glasses | 5 glasses | 4 glasses | 3.33 glasses |
| 1.5 L | 1500 ml | 10 glasses | 7.5 glasses | 6 glasses | 5 glasses |
| 2 L | 2000 ml | 13.33 glasses | 10 glasses | 8 glasses | 6.67 glasses |
| 2.5 L | 2500 ml | 16.67 glasses | 12.5 glasses | 10 glasses | 8.33 glasses |
| 3 L | 3000 ml | 20 glasses | 15 glasses | 12 glasses | 10 glasses |
| Glasses | Litres | ml | Fl oz (US) | Daily goal % |
|---|---|---|---|---|
| 1 glass | 0.25 L | 250 ml | 8.45 fl oz | 12.5% |
| 2 glasses | 0.5 L | 500 ml | 16.9 fl oz | 25% |
| 3 glasses | 0.75 L | 750 ml | 25.4 fl oz | 37.5% |
| 4 glasses | 1.0 L | 1000 ml | 33.8 fl oz | 50% |
| 6 glasses | 1.5 L | 1500 ml | 50.7 fl oz | 75% |
| 8 glasses | 2.0 L | 2000 ml | 67.6 fl oz | 100% ✓ |
| 10 glasses | 2.5 L | 2500 ml | 84.5 fl oz | 125% |
| Bottle size | ml | 150ml glass | 200ml glass | 250ml glass | 300ml glass |
|---|---|---|---|---|---|
| Small bottle | 330 ml | 2.2 glasses | 1.65 glasses | 1.32 glasses | 1.1 glasses |
| Standard bottle | 500 ml | 3.33 glasses | 2.5 glasses | 2 glasses | 1.67 glasses |
| Large bottle | 750 ml | 5 glasses | 3.75 glasses | 3 glasses | 2.5 glasses |
| 1L bottle | 1000 ml | 6.67 glasses | 5 glasses | 4 glasses | 3.33 glasses |
| 1.5L bottle | 1500 ml | 10 glasses | 7.5 glasses | 6 glasses | 5 glasses |
| 2L bottle | 2000 ml | 13.3 glasses | 10 glasses | 8 glasses | 6.67 glasses |