Check URL Safety

Overview

The `url` value is trimmed, given `https://` when it has no scheme, and parsed; its lowercased hostname becomes `domain`. Paths, ports and query strings are ignored, so `example.com/page?x=1` and `https://example.com` give the same answer. A value that cannot be parsed returns 400.

The lookup tries the exact hostname first, then each parent domain in turn, stopping before the bare TLD: for `a.b.example.com` it checks `a.b.example.com`, `b.example.com` and `example.com`. The first hit sets `isBlocked` to true, `safetyRating` to `unsafe`, `matchedDomain` to the listed name and `category` to its label. With no hit, `category` and `matchedDomain` are null and the rating is `safe`, which means only that the domain is absent from these lists; the page itself is never fetched or scanned.

The blocklist is rebuilt daily from five StevenBlack hosts files: the unified ads and malware list, then the fakenews, gambling, porn and social extensions. A domain on several of them keeps the first category in that order, so `category` is always a single label.

`categories` comes from a separate, larger index combining those five lists with eight Block List Project lists. It gathers every category for the hostname and all its parents, so it can be non-empty while `isBlocked` is false. A popular domain keeps the Block List Project porn label only when StevenBlack's porn list agrees, to limit false positives on mainstream sites. If the index cannot be read, `categories` is null rather than failing the call. On the Free plan `category` and `categories` are null.

Live Test Check URL Safety Source →

Formula

One function covers the whole catalog: the first argument names the source, the next are its inputs, and the field after them says which single value lands in the cell. Formulas covers the grammar that applies to all of them.

=VERVE("contentfilter", A2, "domain")

=VERVE.CALL("contentfilter", A2, "domain")

A2 holds the url you are looking up. Drag the formula down and each row resolves on its own.

With literal values

Nothing has to come from a cell — typed values work the same way.

=VERVE("contentfilter", "https://example-gambling-site.com/play", "domain")

=VERVE.CALL("contentfilter", "https://example-gambling-site.com/play", "domain")

Inputs

Required inputs are positional, in the order below, followed by the field. Everything else is passed as a "name", value pair after that — the same shape as SUMIFS. Premium inputs are accepted on every plan but only take effect on plans that include them.

What lands in your sheet

The field — the argument after the inputs — is what makes the formula resolve to one cell. Its value is a dot-path from the table below, so swapping it is how you pull a different value — one formula per column.

Seeing everything at once

Leave the field out and the formula returns the whole response instead: two columns, field name on the left and value on the right, spilling from the cell you typed in.

=VERVE("contentfilter", A2)

=VERVE.CALL("contentfilter", A2)

Response fields

Paths are relative to data. Each one is exactly what the field argument accepts, so swapping it is how you pull a different value into a cell. On a plan without a Premium field the cell reads #PREMIUM(field) rather than a value, so a locked field never looks like a real answer.

Filling a whole column

Both platforms make one batched call for a column rather than one request per cell, and both cost the same — 2 credits per row looked up. How you write it differs, because the two runtimes batch at different points.

=VERVE("contentfilter", A2:A100, "domain")

In Google Sheets, give the arguments ranges and the answers spill down from the cell you typed in. Custom functions there run synchronously and in isolation, so dragged cells cannot be coalesced — the range form is how a column becomes one call. The field is required here: a per-row two-column table has nowhere to spill. Use a full column per input (A2:A100, not A2) — a single-cell reference is read as row 1 only and the rest of the column comes back blank.

In Excel, type the formula once and fill down — no range form and none needed, because its runtime is asynchronous and the add-in coalesces the calls a fill produces into a single batched request. Do not hand VERVE.CALL a range: Excel flattens it into positional arguments, so A2:A100 arrives as a hundred separate arguments and the cell reads #ERR rather than filling.

Either way, column A holds your url values and the answers land beside them, one row each, blank rows skipped.

When a cell doesn't fill

A failed lookup returns readable text starting with #ERR rather than a spreadsheet error, because Excel cannot show a custom message on a real error — you would get a bare #VALUE! with no reason. The trade-off is that IFERROR() will not catch it; test with LEFT(cell, 4) = "#ERR" instead. Error handling covers the rest.

Before the formula works

The add-in reads the API key you saved once in the side panel — the key never goes in the formula, so a shared sheet does not leak it and a collaborator without access simply sees the last calculated values.

1. Install the add-in for Google Sheets or Excel.
2. Open the side panel and sign in, or paste a key from your dashboard.
3. Type the formula above into any cell.

Use cases

Parental Controls

Block inappropriate content for children including adult sites, gambling, and fake news

Workplace Filtering

Keep employees focused by detecting social media and entertainment sites

Safe Browsing Apps

Build family-friendly browsers that warn users about unsafe content

Content Moderation

Screen user-submitted URLs before allowing them on your platform

Other ways to use Check URL Safety

Set up Check URL Safety on VerveSheets, or reach the same source a different way. Your VerveSheets account and credits work on all of them — one key, one balance.

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