I built a simple tool because I was tired of watching restaurants guess their margins

I’ve been spending a lot of time talking to small restaurant owners lately, and one thing kept coming up over and over:

They don’t actually know their margins.

Not in a precise, real-time way.

Most are using spreadsheets. Some update them weekly. Some monthly. Some… never update them after creating them.

And the problem isn’t that they don’t care — it’s that keeping them accurate is a pain:

Ingredient prices change constantly
Every change means recalculating recipes manually
Supplier invoices come in different formats
It’s time-consuming, so it gets ignored

Meanwhile, their actual margins are quietly drifting.

A dish that was profitable last month might not be today — and they won’t notice until it’s too late.

So I started building something simple:

https://margin-guard-xi.vercel.app/

A tool that:

Tracks ingredient costs
Updates recipe margins automatically when prices change
Flags low-margin dishes
Lets you upload invoices instead of manually updating spreadsheets

No POS. No complex system. Just food cost + margins.

What surprised me most during this process:

Restaurant operators don’t want “more software.”
They want less guessing.

They don’t care about dashboards packed with features.
They care about questions like:

“Which dishes are actually making me money?”
“What changed this week?”
“Where am I losing margin without realizing it?”

I’m still early and figuring things out.

If you’ve worked in restaurants or built for this space, I’d love to hear:

How do you (or your customers) track food costs today?
How often do those numbers actually get updated?
What’s the most annoying part of the process?

Trying to understand the real workflow before overbuilding anything.

Happy to share what I’ve learned so far if it’s helpful.