> For the complete documentation index, see [llms.txt](https://guides.noloco.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://guides.noloco.io/data/collections/formulas.md). # Formulas Overview of formula fields in Noloco — what they are, when they recalculate, and what types of values they output. A **formula field** contains a value calculated from a spreadsheet-like expression. Formulas operate on other fields on the same record — including other formula fields — supporting mathematical, logical, text, and date-based processing. For example, a *full name* field on the **User** table could concatenate the *first name* and *last name* fields. This page covers the concept and lifecycle. For task and reference content, see: * [Creating a formula field](/data/collections/formulas/creating-formula-fields.md) — step-by-step setup * [Examples](/data/collections/formulas/examples.md) — common formula recipes * [Troubleshooting](/data/collections/formulas/troubleshooting.md) — fixing formulas that don't work * [Operators reference](/data/collections/formulas/operators.md) — all supported operators, grouped by category: * [Date & time operators](/data/collections/formulas/operators/date-and-time.md) * [Logic operators](/data/collections/formulas/operators/logic.md) * [Math operators](/data/collections/formulas/operators/math.md) * [Text operators](/data/collections/formulas/operators/text.md) ### When do formulas calculate? A formula's value for a given record recalculates when any of the following occur: * The formula field is created * The formula is updated * A new record is added * A field referenced in the formula is updated If a formula doesn't reference any other fields, it will only recalculate when: * The formula is added initially * The formula is edited * The record is initially created ### Output types When a formula is added or updated, Noloco inspects the output and assigns a type based on the result pattern. The possible output types are: * **Boolean** — formula must return `true` or `false` * **Date** — formula must return a value wrapped in the `TODATE` operator * **Decimal** * **Integer** * **Text** --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://guides.noloco.io/data/collections/formulas.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.