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TwinaForms Help

Writing formulas in TwinaForms.

Formulas compute a field's value live as users fill the form — from simple concatenations like a full name, to totals, date math, and conditional messages. This page is a practical reference with copy-paste examples.

Where formulas work

Turn any Text or Number field into a formula field from the Designer's Element Properties panel. The field becomes read-only in the published form and recomputes every time a source field changes.

  • Recalculates live as the user types.
  • Submits the computed value to Salesforce along with everything else.
  • Formulas can reference input fields, but not other formula fields (no formula‑to‑formula chains in v1).
  • Not yet available inside repeat groups.

Syntax basics

Field references

Wrap a field's Internal Name (ID) in curly braces. Internal IDs are auto-generated and look like text2, number4, email5, checkbox11, radio10 — not the friendly label you typed.

{text2}
{number4}
{checkbox11}

You don't have to type them. In the formula editor use the Insert field dropdown (the list shows each field's friendly label with its internal ID in parentheses) and click Insert — the correct reference is placed at the cursor.

Literals

  • "Hello" — string (double quotes).
  • 42, 3.14, -1 — numbers.
  • true, false — booleans.

Function calls

Function names are uppercase. Arguments are separated by commas.

IF({isVip}, "Priority", "Standard")
CONCAT({firstName}, " ", {lastName})
Common pitfall with IF: use == for equality, not a single =. A single equals sign is not a valid operator here and the formula will fail.
❌ IF({status} = "Open", "Yes", "No")
✅ IF({status} == "Open", "Yes", "No")

Operators

Arithmetic

+ - * / 
{quantity} * {unitPrice}
({subtotal} + {tax}) - {discount}

Comparison

== != < > <= >=

String comparisons are case-sensitive. Use IF({rating} == "Hot", …) with the exact picklist value.

Logical

and or not 
IF({total} > 100 and {isMember}, "Member discount", "")

Examples

Copy, paste into a Text or Number formula field, and replace the field references with yours.

Field names in these examples are placeholders. Below we use readable names like {firstName} or {quantity} to make the logic easy to follow. In your form, the real references look like {text2}, {number4}, etc. Use the Insert field dropdown in the Designer to pick the right one — it inserts the correct internal ID for you.

Full name from two fields

Text formula. Uses CONCAT so "John" + " " + "Doe" becomes "John Doe".

CONCAT({firstName}, " ", {lastName})

Line total

Number formula. Multiplies quantity by unit price.

{quantity} * {unitPrice}

Line total with tax, rounded to cents

Number formula. The outer ROUND keeps the result to two decimals.

ROUND({quantity} * {unitPrice} * 1.17, 2)

Equality check — IF(A == B, …)

Text formula. Compare a field to a literal value using ==. String comparisons are case‑sensitive, so match the exact picklist or input value.

IF({rating} == "Hot", "Contact today", "Regular follow-up")

VIP greeting

Text formula. Shows a personalized line only for members.

IF({isMember},
   CONCAT("Welcome back, ", {firstName}, "!"),
   CONCAT("Hello, ", {firstName}))

Default to "N/A" when a field is empty

Text formula. COALESCE returns the first non-blank argument.

COALESCE({nickname}, {firstName}, "N/A")

Age from a date of birth

Number formula. Approximate age using year difference.

YEAR(TODAY()) - YEAR({dateOfBirth})

Discount band

Text formula. Nested IF forms a simple tiered rule.

IF({orderTotal} >= 1000, "Gold",
 IF({orderTotal} >= 500, "Silver",
 IF({orderTotal} >= 100, "Bronze", "Standard")))

Shipping fee rule

Number formula. Free shipping above $100, otherwise flat $9.90.

IF({orderTotal} >= 100, 0, 9.90)

Case reference

Text formula. Builds a unique-looking id the user can quote in support.

CONCAT("REF-", YEAR(TODAY()), "-", {email})

Limits & gotchas

  • String comparisons are case-sensitive. "Hot" == "hot" is false.
  • Empty fields become null, not an empty string. Wrap with COALESCE({field}, "") if you need a safe default.
  • Dates are browser-local. A user in Tel Aviv and one in New York can see different TODAY() values for a few hours each day.
  • No formula-to-formula references. If you need a nested calculation, inline it in a single expression.
  • No support inside repeat groups yet. Place formulas on top-level fields only.
  • Formula fields ignore prefill. The source fields prefill normally and the formula recalculates from them.
  • Invalid input returns null. VALUE("hello") is blank, not zero.
Tip: Build formulas incrementally. Start with the simplest case, publish, fill the form, confirm the computed value in the Submission Logs, then extend. Logs show the final computed value as submitted, which makes it easy to spot where a nested expression went wrong.