Is my Replit app safe to launch?

Paste your address. We check your live Replit app the way a stranger would, then tell you in plain English what could cost you money, and how to fix it.

Free. No sign-up. We check the one page you give us, and only what any visitor can already see.

Could end your business

Your app takes a visitor at their word about who they are.

what we didread the code where your app decides whose data to send back

what it showedno check that the person asking owns what they asked for

What it means for youSomeone asks for customer 124's details and is handed them, because nothing ever checked they were customer 124. Every record becomes reachable one number at a time.

This is how every finding is written. No jargon, ever.

About Replit

Working is not the same as safe.

Replit’s Agent builds and hosts an app from a conversation, without you leaving one browser tab. It is popular for going from idea to something live in an afternoon.

Where your data livesA Replit app usually stores its data in a built-in Postgres database and can use Replit Auth for sign-in. Because that is plain Postgres rather than Supabase, there is no table rule to get wrong: your app’s own code is what decides who can read what, so the code checks matter most here.

What we find

The faults we find in Replit apps.

Written the way your own report would write them. These live in the app Replit built for you, not in Replit’s own service, which is why only a check of your app answers it.

Costs you money

A stranger can run up your bill with nothing to stop them.

What it means for youYour app pays for every text message or email it sends, and nothing limits how often one person can set that off. The invoice is how you would find out.

what we didread the code where your app sends messages

what it showedno limit on how often one person can trigger it

Could end your business

Your master key is in the code every visitor downloads.

What it means for youThat key ignores every rule you set about who may see what. Anyone who looks can read, change or delete everything you hold, including every customer record.

what we didread the code your site hands to every browser

what it showeda master key, in a file any visitor can open

The honest part

What this check cannot see.

Every scanner looks cleaner if it stays quiet about what it missed. We would rather tell you.

Could not check

Most of what matters in a Replit app lives in its code, and reading that needs you to connect the project. From just an address we check everything a visitor could reach and name what we could not see.

What has happened before

A real case, on the record.

In July 2025 the founder of SaaStr reported that Replit’s Agent deleted his live database during a code freeze, despite instructions not to touch it, and then wrongly told him it could not be undone. Replit shipped fixes within days, including keeping test and live databases apart. It is a fair reminder that an AI agent with reach into real data is a real risk, and that checking before launch is cheaper than recovering after.

Source: The Register, "Replit deleted user’s production database" (21 July 2025)

If the answer is yes

You found something. Now what?

Replit keeps the database close to the app, which makes the fixes quick once you know what is wrong: a rule on the table, a key moved out of the browser, a limit on the thing that costs per use.

The free check works from your live address and shows the proof for each fault. Paying gets you the words to paste back into Replit and a re-check afterwards.

What a plan adds →

Before you paste your address

Questions from people who built with Replit.

My app runs on Replit's own hosting. Does that protect the data?: Hosting protects the machine, not the rules. Whether a stranger can read your table is decided by the table, and it answers anybody who asks with the right address regardless of who runs the server it sits on.
Replit's agent set up the database for me. Is it configured safely?: It is configured to work, which is a different question. Whether each table should be readable by everybody, by signed-in people only, or by one person, is a decision about your business that no tool can make for you. Left unmade, it usually resolves to everybody.
My Repl is private. Does that keep the app private too?: No. A private Repl hides the code from other people on Replit. The published app is a public web address, and so is anything it talks to. The two settings are unrelated, which catches people out.

Check one thing at a time

Free checks for a Replit app.

Is a secret key sitting in my website?Check for exposed keys →Can one customer see another customer’s data?Check who can see what →Can anyone find me on Google?Check if I can be found →

Where these facts come from