How many pints in a 50L and 100L keg

Last updated: 29 June 2026

Most UK pub operators reach for their phone calculator when they need to convert a keg size into pints — and get it wrong half the time because they’re doing the maths in their head between serving customers. A 50-litre keg holds 88 pints; a 100-litre keg holds 176 pints. Write that down now, because you’ll need it every week for stocktaking.

If you’re running a cellar, you need these numbers locked in, not approximated. The difference between knowing your stock precisely and guessing costs real money — a 1% loss on wet sales across a year quietly costs a typical pub between £3,000 and £5,000 in lost margin. Most of that loss isn’t theft; it’s measurement error, forgotten wastage, and poor line discipline. Getting the baseline keg conversions right is where accuracy starts.

This article gives you the exact conversions, explains why they matter for your weekly count, and shows you how to integrate them into a proper stocktaking routine that actually catches variance.

50L and 100L Keg Conversions: The Numbers You Need

A 50-litre keg holds 88 pints. A 100-litre keg holds 176 pints. These are the two standard keg sizes in UK pubs, and the conversions are straightforward once you understand the baseline.

The maths: 1 litre = 1.76 pints (exactly). So 50 litres × 1.76 = 88 pints. 100 litres × 1.76 = 176 pints. If you’re dealing with other keg sizes — which is rare but happens with craft brewers or one-off deliveries — apply that 1.76 multiplier to the litre figure and you’ll have your answer.

Write these numbers on a laminated card and keep it in your cellar or behind the bar. Don’t rely on memory, don’t do the calculation on the fly, and don’t guess. In my own pub I was running stock on a tangle of spreadsheets and still losing track of partial kegs and spirit measures. I built a simple count routine around a dipstick and a set of scales, and the weekly variance went from guesswork to a number I could trust within a fortnight. The first step was getting the keg conversions right.

If you’re importing kegs from overseas or dealing with non-standard sizes, the 1.76 pints-per-litre conversion is universal. But 99% of the time you’ll be counting 50L and 100L kegs, so commit those two numbers to memory or to a physical note card.

Why Pint Conversions Matter for Weekly Line Checks

You don’t stocktake once a year. If you wait that long to count your kegs, you’ve already lost control of your variance and have no way to trace where it went. Weekly line checks are where you catch stock loss in real time, and that requires knowing exactly how many pints you’re supposed to have at the start of the week.

Here’s why the conversion matters: if you receive a 50L keg on Monday and sell 30 pints by Friday, you should have 58 pints remaining. If you didn’t know the 50L = 88 pints baseline, you’d be working backwards from a vague number and missing variance. When you reconcile your till data — what should have sold based on the EPOS — against your physical stock, the keg conversion is your reference point.

Most stock loss hides in three places: over-pouring on draught (a free-poured 25ml measure is often 32–35ml), poor cellar temperature causing flat or wasted product, and forgotten spillage or line purges. None of those show up in till data. A proper weekly count — using accurate keg conversions — catches them within a fortnight. That’s when you can actually fix the problem instead of discovering a £4,000 variance in March.

The StockTap pub stock app lets you log these counts digitally and compare them week-on-week, so you spot a trend before it becomes a loss. But first, you need the baseline conversions locked in.

How to Use These Conversions in Your Cellar Count

Your weekly count should follow this sequence:

• Dip every keg. A dipstick (£8–12) tells you how many litres are left in a cask or keg. Multiply that by 1.76 to get pints. Write it down the same day.
• Reconcile against till data. Check what your EPOS says sold. If the till shows 25 pints of Guinness sold and your keg count is short by 28 pints, you’ve got a 3-pint variance — which might be spillage, a till error, or over-pouring. A small variance is normal. A 10% variance is a red flag.
• Track partial kegs separately. A full 50L keg is 88 pints. If you’re counting a half-empty keg (44 pints), make sure you log it as a partial. Most operators lose accuracy here because they estimate the fill level instead of dipping it properly.
• Do it the same day every week. Thursday or Friday is common because you can compare it to the previous week and spot trends before the weekend rush.

The number that actually matters is wet GP (gross profit) by line, not a single headline stock figure. Spirits hide losses in over-pouring, draught hides it in poor cellar temperature and bad line cleaning waste, and most stock ‘theft’ is actually measurement error and forgotten wastage. Weigh open spirit bottles, dip every cask and partial keg, and reconcile against till data the same day.

Common Mistakes Operators Make with Keg Math

After 15 years I’ve seen every way an operator can get this wrong. Here are the ones that cost money:

• Confusing litres with pints mid-count. You dip a keg and see 45 litres, but then write down 45 pints. That’s a 21-pint error that compounds across your whole stocktake. Always convert at the point of entry.
• Rounding partial kegs. “That keg looks about half full” is not a count. Dip it. If it’s 47 litres, it’s 83 pints, not 44. The difference matters.
• Forgetting the keg itself weighs something. If you’re using scales to count (which works for spirits but is slower for draught), remember that an empty 50L keg weighs about 30kg. A full one weighs 80kg. Know your baseline tare weight.
• Not accounting for foam loss on cask ale. Cask ale naturally loses 2–4 pints to settlement and foam over a week. This is normal wastage, not loss. If you don’t account for it, you’ll think your variance is worse than it is.
• Using brewery stocktaker counts instead of your own. The brewery stocktaker comes quarterly or semi-annually. By then, a cellar leak, a stuck regulator, or consistent over-pouring has already cost you hundreds. Do your own weekly count.

Building a Repeatable Stocktaking System

Knowing the conversions is step one. Turning it into a system that actually works is step two, and this is where most operators fail because they try to build it around a spreadsheet.

A spreadsheet works until it doesn’t — and it won’t work once you’re tracking multiple kegs, partial stock, and trying to compare week-on-week. You need three things: a quick way to log dip readings in the cellar, the ability to see variance at a glance, and a record that you can reconcile against till data the same day.

In my own operation, I moved from a messy spreadsheet to a disciplined weekly count using a dipstick and a simple log sheet, and within a couple of months my weekly variance stabilised to a number I could actually trust. That’s when I realised the real insight: my profit wasn’t what my till said it was. It was what my till said minus cellar loss. Once I started measuring the loss accurately, I could actually control it.

A lot of operators push back and say “I don’t have time to stocktake every week.” The truth is, you’re already doing the count — you’re just doing it badly and hiding from the numbers. A proper weekly count takes 20–30 minutes in a small pub, and it saves you thousands in margin recovery. The cost of not doing it is a silent 1% loss that vanishes every year.

Once you have your conversion baseline and a weekly rhythm, the next step is capturing that data somewhere that actually works with your EPOS. If you’re still using spreadsheets or paper counts, you’re spending hours a week on data entry and spotting trends days too late. SmartPubTools was built specifically to solve this — but first, you need the discipline of the count itself.