Common Errors and Troubleshooting

Use this page to troubleshoot formula errors. Find the closest error type first, then compare your formula with the safer pattern.

Type mismatch

Wrong example:

If Amount is a number, you may need to convert it to text:

"Amount: " + format(prop("Amount"))

Empty date errors

Wrong example:

formatDate(prop("Due Date"), "YYYY-MM-DD")

Safer pattern:

if(empty(prop("Due Date")), "Not set", formatDate(prop("Due Date"), "YYYY-MM-DD"))

Mixing lists and single values

Person, relation, and multi-select properties often return lists.

Wrong mental model:

prop("Assignee").name()

More reliable pattern:

prop("Assignee").map(current.name()).join("、")

If you only want the first item:

prop("Assignee").first().name()

dateBetween() is off by one day

If you use now(), the specific time is included in the calculation. If your due date has no time, the result may feel unintuitive.

For task due-date checks, prefer:

dateBetween(prop("Due Date"), today(), "days")

Instead of:

dateBetween(prop("Due Date"), now(), "days")

Formula depth is too deep

Notion's official error explanation notes that formula depth increases when formulas reference formulas, formulas reference rollups, or rollups reference formulas again. The depth limit is 15 layers.

Ways to fix it:

1. Reduce chained references between formulas.
2. Split overly long formulas into databases closer to the original data source.
3. Avoid passing the same calculated value back and forth between multiple rollups.
4. For large systems, use a three-layer structure: raw data -> intermediate metrics -> display results. Do not nest endlessly.

Regex escaping errors

When writing regular expressions inside Notion strings, backslashes usually need to be doubled.

Match numbers:

match(prop("Text"), "\\d+")

Match a dot:

test(prop("Domain"), "\\.")

Automation return type errors

If an automation needs to fill a date, your formula must return a date, not a text-formatted date.

Wrong example:

formatDate(dateAdd(today(), 1, "days"), "YYYY-MM-DD")

Correct direction:

dateAdd(today(), 1, "days")