Sell 5 ml without losing track of the 100 ml bottle.
Carboy keeps your bulk stock as one pool, measured in ml or grams, and sets every size's stock in Shopify from it. A 20 ml order takes 20 ml, and your 2 ml samples know about it.
Free for one pool. Billed through Shopify after that.
Try it · Oud Reserve, 100 ml bottle60.0 ml left · 2 ml kept back
0255075100 ml
2 ml sample29
5 ml decant11
10 ml travel5
Press a button: the other sizes recount.
“If I sell both my 20ml it'll show that it's out of stock on 20ml, but in reality I still have 60ml left.”
A decant seller on the Shopify Community forum, 2021. The thread has no answer. Carboy is the answer.
Three steps, then you forget it's there
- 01Pick a productCarboy reads the size from each variant name: "Sample / 2ml", "10 ml Travel", "250g bag", "4 fl oz". You fix anything it can't read.
- 02Say what's on the shelf143.5 ml, 3.42 kg, whatever the scale says. Keep a little back for spills and testing if you like.
- 03Sell as usualOnline, in person with POS, refunds and cancellations: each one moves the pool, and every size is recounted within seconds.
Made for shops that portion
| You sell | From | In sizes like |
|---|---|---|
| Fragrance decants | a 100 ml bottle | 2 · 5 · 10 ml |
| Loose-leaf tea | a 5 kg sack | 25 · 50 · 100 g |
| Coffee beans | a roasted batch | 250 g · 1 lb |
| Spices and herbs | a 2 kg bag | 50 · 100 g |
| Refill shops | a 20 l drum | 500 ml · 1 l |
Stock apps break. This one is built not to.
Every order counts onceShopify sometimes sends the same order twice. Carboy remembers what it has already taken.
It asks before it overwritesIf someone changes stock by hand, Carboy flags the pool and waits for you instead of guessing.
It checks itself every nightAt 03:00 it compares every size with the pool and tells you about anything that doesn't add up.
Uninstalling changes nothingYour last numbers stay in Shopify. Nothing drops to zero on the way out.
Pricing
| Free | $0 | One pool, every feature. Enough to see if it fits. |
|---|---|---|
| Starter | $12 / month | Up to 25 pools, morning email summary. |
| Pro | $29 / month | Unlimited pools, in-person sales with POS, several stock locations. |
Questions
What if a variant name has no size in it?
You type it once, or leave that variant out of the pool, like a sealed full bottle.
Can one pool feed several products?
Yes. A tea sack can feed a 50 g pouch product and a tasting set at the same time.
I sell in ounces and grams. Is that a problem?
No. Carboy converts between ml, l, fl oz, g, kg, oz and lb inside the same pool.
Does it work with Etsy?
Not yet. Shopify comes first. If you need Etsy, write to us and say so; it decides what we build next.
What happens to my stock if I uninstall?
It stays exactly as Carboy last set it. We delete our copy of your pools 48 hours later.