Menstrual Flow Volume Tracker
Estimate how much blood you lose across your whole period — in millilitres — by logging your menstrual cup readings or your pads and tampons day by day, and see whether your flow is light, normal, or heavy.
Everyone’s flow is different, and it changes from cycle to cycle. This tracker gives you a helpful estimate in millilitres — great for spotting a heavy period and for talking to your doctor — but it can’t diagnose a cause. If your flow worries you, please see a healthcare provider.
Each time you empty your cup, read the mL from its markings and add it here. Enter one total per day (or add up all empties for that day). Days you leave blank count as zero.
For each day, enter how many pads and tampons you used and how soaked they typically were. Not exact? A close estimate still works well.
Log at least one day above, then estimate to see your total flow volume and what it means.
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Where your volume sits
Your flow, day by day
Most people flow heaviest on days 1–2, then taper. Here’s your pattern:
What to do next
This is an estimate, not a lab measurement or a diagnosis. Product capacities and how soaked they get vary a lot, so treat the number as a guide to the overall picture rather than an exact figure. It can’t tell you why a period is heavy. Please see a provider if your flow is heavy, changing, or worrying you — and seek urgent care for very heavy bleeding with dizziness, fainting, or a racing heart.
How the menstrual flow volume tracker works
Most people have no idea how much they actually bleed during a period — and that’s understandable, because it’s hard to measure. This tracker gives you a realistic estimate in millilitres using two methods. The most accurate is a menstrual cup: because cups have volume markings, every time you empty yours you can read the mL directly and add it up across your period. If you use pads and tampons, the tracker estimates volume from how many you used, their absorbency, and how soaked each one was — using the standard capacities that products are designed to hold.
It then totals your whole period, compares it to the clinical thresholds for light, normal, and heavy bleeding, and shows your day-by-day pattern. If you’d rather score your flow using clot size and saturation instead, our Period Blood Clot & Heavy Period Calculator uses the validated PBAC method and pairs perfectly with this one.
Quick answer
A typical period is about 30–40 mL of blood (two to three tablespoons) across the whole cycle, and anything up to around 80 mL is considered normal. Losing more than 80 mL, or bleeding for more than 7 days, counts as a heavy period (menorrhagia) and is worth discussing with a doctor.
How much blood is normal in a period?
| Flow level | Blood loss per period | Everyday comparison | What it means |
|---|---|---|---|
| Very light | Under 10 mL | A few teaspoons | Light, or spotting |
| Normal | 10–80 mL | Up to ~1/3 cup | Typical range (average ~35 mL) |
| Heavy | 80–150 mL | 1/3 to 2/3 cup | Menorrhagia — worth checking |
| Very heavy | Over 150 mL | More than 2/3 cup | See a provider; check for anemia |
How much do period products hold?
Knowing your products’ capacity is the key to estimating volume. A fully soaked regular tampon or pad holds roughly a teaspoon (about 5 mL); a super tampon holds around 12 mL; a maxi or overnight pad can hold 10–15 mL; and menstrual cups typically hold 20–30 mL depending on size. That’s why menstrual cups make measuring so much easier — you’re reading an actual volume rather than guessing at saturation. The tracker uses these standard capacities and adjusts for how soaked each item was.
Signs your period might be heavy
Beyond the millilitres, the everyday signs of a heavy period are worth knowing: soaking through a pad or tampon every hour for several hours in a row, needing to double up on protection, waking overnight to change, passing clots bigger than a quarter, bleeding for more than 7 days, or feeling tired, breathless, and pale — which can signal iron-deficiency anemia from blood loss. Heavy periods affect roughly one in five people who menstruate and are very treatable, so they’re worth raising rather than tolerating.
A worked example
Suppose you track your cup over a five-day period and read 25 mL, 30 mL, 20 mL, 10 mL, and 5 mL. That totals 90 mL — just over the 80 mL heavy threshold, so it’s worth a conversation with your provider. By contrast, seven fully soaked regular tampons across a period come to about 35 mL, comfortably in the normal range. Tracking across a couple of cycles gives the clearest picture.
Related maternal health calculators
This tool is part of the Maternal Health Calculators hub. These companion tools cover cycle tracking, ultrasound dating, and pregnancy planning — each answers a different question, so choose whichever fits where you are.
Frequently asked questions
On average about 30–40 mL of blood — two to three tablespoons — across the whole period, though anything up to around 80 mL is normal. Losing more than 80 mL is considered a heavy period.
The easiest accurate way is a menstrual cup with mL markings — read and add up the volume each time you empty it. If you use pads or tampons, you can estimate from how many you used, their absorbency, and how soaked they were, which is what this tracker does.
Clinically, losing more than about 80 mL of blood per cycle, or bleeding for more than 7 days. Practical signs include soaking a pad or tampon every hour, doubling up on protection, large clots, and feeling drained.
A fully soaked regular pad or tampon holds roughly a teaspoon (about 5 mL). A super tampon holds around 12 mL, and a maxi or overnight pad 10–15 mL. Menstrual cups typically hold 20–30 mL depending on size.
Yes. Because cups collect the fluid and have volume markings, you read an actual millilitre amount rather than estimating saturation. Adding up each empty across your period gives the closest at-home measurement.
Flow is usually heaviest on the first day or two as the uterine lining sheds fastest, then tapers over the following days. This pattern is normal, and the day-by-day chart in this tracker shows yours.
Yes. Losing a lot of blood each cycle can deplete your iron and lead to iron-deficiency anemia, which brings tiredness, breathlessness, and pallor. A simple blood test checks for it, and it’s very treatable.
No — only about half of menstrual fluid is blood. The rest is uterine lining tissue, mucus, and other secretions. Clinical thresholds like 80 mL refer to blood loss, which is what this tracker estimates.
It’s a solid estimate based on standard product capacities and clinical thresholds, and a menstrual cup makes it quite accurate. Still, it’s a screening guide, not a lab measurement or diagnosis. Your provider interprets it with your history.
See a provider if you regularly soak through protection hourly, estimate over 80 mL, bleed more than 7 days, pass large clots, or feel drained. Seek urgent care for very heavy bleeding with dizziness, fainting, or a racing heart.
Methodology
This tracker estimates menstrual blood loss two ways. In menstrual-cup mode, it simply sums the millilitre readings you enter for each day, which is the closest practical measurement of collected fluid. In pads-and-tampons mode, it multiplies each product by its standard fully soaked capacity — regular pad/tampon about 5 mL, super tampon about 12 mL, maxi or overnight pad 10–15 mL — then adjusts by how soaked each was (lightly stained about 25%, moderately about 50%, fully soaked 100%). Totals are summed across all logged days. Interpretation follows widely used thresholds: up to about 80 mL of blood loss per cycle is considered normal (average roughly 30–40 mL), 80 mL or more indicates a heavy period (menorrhagia), and over about 150 mL is very heavy. These values reflect blood loss rather than total fluid, since only about half of menstrual fluid is blood. All results are screening estimates for education, not a diagnosis, and are not a substitute for assessment by a qualified provider.
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References & trusted sources
- NHS — Heavy periods
- ACOG — Heavy Menstrual Bleeding (FAQ)
- CeMCOR (UBC) — Measuring & assessing menstrual flow
- Mayo Clinic — Menorrhagia (heavy menstrual bleeding)
Last reviewed & updated: July 2026.