02-05-2026, 12:46 PM
The easiest DIY method is still water displacement, but with someone on HRT you have to be extra consistent because breast tissue can change from swelling, tenderness, weight shifts, and normal hormone-related fluid retention.
Use a digital kitchen scale, a bowl or container, and warm water.
Put the water-filled bowl on the scale, hit tare/zero, then lean forward and lower one breast into the water to the same point each time. Try not to press down or touch the sides/bottom. The increase in grams is roughly the breast volume in cc/ml.
Example: 450 grams = about 450 cc/ml of displaced volume.
Do each side 3 times and average it.
The key is measuring the same way every time:
For someone on HRT, I’d also write down notes like:
Date Left Right Notes
May 2 ___ cc ___ cc sore, swollen, weight stable
Next month ___ cc ___ cc less tenderness, same method
A tape measure can help too, standing bust, leaning bust, underbust, and breast width, but tape measurements are more about shape and projection, not true volume.
So yes, water displacement is probably the best easy DIY method, but I’d use it for comparison over time, not as an exact medical number. On HRT, the trend matters more than one single measurement.
Use a digital kitchen scale, a bowl or container, and warm water.
Put the water-filled bowl on the scale, hit tare/zero, then lean forward and lower one breast into the water to the same point each time. Try not to press down or touch the sides/bottom. The increase in grams is roughly the breast volume in cc/ml.
Example: 450 grams = about 450 cc/ml of displaced volume.
Do each side 3 times and average it.
The key is measuring the same way every time:
- Same container
- Same water level
- Same posture
- Same time of day
- Same amount of breast submerged
- Same side measured first
- No pushing or compressing the breast
For someone on HRT, I’d also write down notes like:
Date Left Right Notes
May 2 ___ cc ___ cc sore, swollen, weight stable
Next month ___ cc ___ cc less tenderness, same method
A tape measure can help too, standing bust, leaning bust, underbust, and breast width, but tape measurements are more about shape and projection, not true volume.
So yes, water displacement is probably the best easy DIY method, but I’d use it for comparison over time, not as an exact medical number. On HRT, the trend matters more than one single measurement.