Bladder Diary Calculator
Enter the totals from your bladder diary and get the six figures clinicians actually read — each checked against typical adult ranges, instantly and privately. Nothing you type leaves this page.
Your 24-hour totals
Count every urination, including overnight.
All voided volumes added together.
Usually the first void of the morning.
Everything you drank in the same 24 hours.
Times you woke at night to urinate.
Night voids plus the first void after waking — that urine was produced during sleep.
Enables the polyuria check (40 ml/kg/24h).
* Required. Averaging three recorded days gives a more reliable result than one.
The hard part isn't the math — it's the three days of measuring
Bladder Journal records every void with automatic timestamps, estimates volumes from sound entirely on-device, separates night-time voids, and computes everything on this page continuously — then exports a PDF for your appointment. Unlimited tracking is free.
Download Bladder Journal — FreeHow each figure is calculated
- Voids per 24 hours — every void counted, day and night. Typical: 4–8.
- Average voided volume — total output ÷ number of voids. Typical: 250–400 ml.
- Maximum voided volume — the largest single void, an estimate of functional bladder capacity. Typical: 400–600 ml.
- Total 24-hour output — all voided volumes added. Typical: 1,200–2,000 ml; above ~40 ml per kg of body weight is termed polyuria.
- Night-time share — night-time volume (including the first void after waking) ÷ total output. Above ~20% (~33% over 65) is described as nocturnal polyuria.
- Intake–output gap — drinks minus output. Normally 500–800 ml leaves the body through breathing, skin and stool.
What the combinations mean — small volumes with high frequency, normal days with heavy nights, and the rest — is covered in how to interpret a bladder diary. If you still need to collect the numbers, see how to measure urine volume at home and a worked bladder diary example.