[hrgdevBuilds]

I built a small tool to clarify how much late fee a landlord can legally charge (and when) in each U.S. state.

Rent laws vary widely: some states set a fixed dollar cap, others a percentage, and a few use only “reasonable” language that’s open to interpretation. Many renters and landlords have no easy way to check what’s actually allowed without reading the statutes themselves.

This project compiles those laws into an instant calculator. Enter rent amount, due date, payment date, and state — it shows the lawful late fee limit, grace period rules, and citation.

It started as a curiosity after seeing conflicting answers online. The goal is transparency, not advocacy; all data is drawn from current state statutes.

The app is lightweight, built in Replit, and runs entirely client-side. I’d be interested in feedback on legal interpretation consistency, data sourcing, or UI clarity.

[limagnolia]

Utah appears to be calculating incorrectly, the text says "10% of rent or $75, whichever is GREATER." But it is doing the opposite, showing the lessor of 10% or $75.

[limagnolia]

New Hampshire has the same bug.

[axus]

I love the ambiguity in who the tool is for. For renters, learning about their rights and fighting illegal fees. For landlords, charging the maximum amount permitted under the law.

[limagnolia]

Or landlords who want to follow the law, but aren't sure what it is, trying to make sure they are doing things right.

[Fraterkes]

If you look at the other tools on the page, there's stuff for property-management and sending rent-reminders. I guess they know what part of their userbase is the most moneyed.

[terminalshort]

It's a tool, and like any tool it should be as neutral as possible.

[candiddevmike]

I thought this would be for tenants, but this seems more geared towards landlords. Most landlords have some kind of SaaS platform that will automate all of this for them as part of rent collection, I don't think you'll get many bites on this TBH.

I'd love to see some kind of 50 state tenant resource center, geared towards providing tenants with advice and legal resources.

[gruez]

Most people aren't lawyers and therefore won't know what statues to read, so they'll need to search/ask AI, which is pretty much what this site does.