Counting by Weight

Counting by weight

Counting 150 tiny M3 screws or 80 LEDs by hand is tedious and error-prone. If Gubbins knows what one of them weighs, it can count a handful for you: put them on a scale, type in the reading, and Gubbins works out how many are there.

Where to find it: Count by weight… in an item's More menu.

Setting it up

Counting by weight needs one thing recorded against the item: its weight — the mass of a single unit. Edit the item and set it once (for example, one M3 screw at 0.5 g), and every future count uses it.

The weight is stored for the item as a whole, so it's worth being reasonably precise: weigh ten or a hundred units on a kitchen scale and divide, rather than trusting a single unit reading on a scale that only resolves to the nearest gram.

💡 Tip Weights are entered and shown in whatever unit you've chosen under language & region — grams, kilograms, ounces or pounds. Gubbins stores them in one canonical unit behind the scenes, so changing the setting never alters your data.

Counting a handful

Open Count by weight… on the item and fill in:

• Weight on scale — the total reading, including anything the parts are sitting in.
• Container weight — optional. The weight of the empty tray, bag or pot. Leave it blank if the parts are loose on the scale, or if you zeroed the scale with the empty container already on it. Pick a container… fills it from the container weights library, so a tray you use often needn't be re-weighed.

Gubbins subtracts the container, divides by the unit weight, and shows the count along with how it compares to the quantity already recorded. Apply count adjusts the item's stock and notes in the activity log how the new figure was arrived at — so a jump in quantity is never unexplained.

Reading the scale automatically

If your scale is connected to Home Assistant, Gubbins can read it directly instead of you reading the display and typing the figure in. The dialog then shows a scale picker and a Read the scale button; the current reading drops straight into Weight on scale, and everything after that works exactly as it does for a typed figure.

There is a second button, Read the container, which does the same thing for the tare: put the empty tray on the scale, press it, and its weight lands in Container weight. Weigh the empty tray, then tip the parts in and press Read the scale — neither figure has to be typed.

This is entirely optional, and typing the reading in yourself always works — nothing here is a prerequisite for counting by weight.

What you need:

1. The optional bridge running, with its URL and an API token filled in under Settings → Sync, and
2. the bridge configured to read Home Assistant, and pointed at your instance.

See Home Assistant integration for setting that up. Once it is running, any Home Assistant entity that reports a weight appears in the picker; choose yours once and Gubbins remembers it on that device.

💡 Tip The choice of scale is remembered per device, so a tablet in the workshop and a phone in the stockroom can each read their own bench scale.

The list of scales is fetched once and then kept for the rest of your session, so opening the dialog for item after item doesn't re-ask Home Assistant each time. If you have just added a scale in Home Assistant and it isn't in the picker yet, use the refresh button beside the picker to fetch the list again — no page reload needed.

Gubbins converts the reading into your chosen weight unit for you, so a sensor reporting kilograms works fine even if you read everything in grams.

⚠️ Heads-up If the sensor reports a unit Gubbins can't convert, it says so rather than guessing — a misread unit could be out by a factor of a thousand and would quietly wreck your stock figure. The same applies if the scale is switched off or unreachable: you get a plain explanation instead of a reading. You can always type the weight in by hand instead.

How much to trust the number

A scale reading is never perfectly exact, so Gubbins tells you how well the reading lines up with a whole number of units rather than quietly rounding:

• Nothing said — the reading landed on a whole number of units. Good count.
• Slightly off — the count is almost certainly right, but something is drifting a little.
• Doesn't line up — the reading sits well away from any whole number of units.

⚠️ Heads-up A reading that doesn't line up usually means one of three things: the container weight is wrong, the recorded unit weight is wrong, or something that isn't one of these parts is on the scale. Gubbins still lets you apply the count — you may know your scale is imprecise — but it's worth checking first.

Accuracy depends on the ratio between your scale's resolution and the unit weight. A scale that reads to 1 g cannot reliably count 0.5 g screws one at a time, but weighing a larger handful averages the error out — the more units on the scale, the tighter the count.

Where it applies

Counting by weight is offered on items using bulk tracking with a finite quantity — the countable, interchangeable units the technique makes sense for. Serialised assets are tracked individually rather than counted, and consumable gauges have their own weigh-in that measures how much is left rather than how many there are.

Related pages

• Container weights — saving the empty weight of trays, jars and spools.
• Items — where a unit weight is recorded.
• Tracking modes — which items can be counted by weight.
• Low stock & gauges — weighing a consumable to gauge what's left.
• Cycle counts & audit day — reconciling stock across a whole location.
• Activity log — where an applied count is recorded.
• Home Assistant integration — connecting a scale so Gubbins can read it.