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Calculate evaluates a formula and writes the result into a target field — live totals, quiz scores, formatted labels, or concatenated text. Use on Calculated blocks (When Always → Calculate) or conditional rules when formulas should run only sometimes.

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When to choose this

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Exact behavior

  • Target receives computed value on every logic recompute when parent When matches.
  • Result feeds later rules in the same pass — calculate Score, then When Score ≥ 80 can match immediately after.
  • Number mode: arithmetic with + - * / %, parentheses, {blockId} tokens, and whitelist functions min(), max(), round(), concat(). Blank or non-numeric tokens make the whole numeric result empty — {qty} + 1 does not become 1 when qty is unanswered. Unknown functions fail closed (empty result).
  • Text mode: string interpolation — tokens replaced; use + between tokens/literals or concat({first}, " ", {last}) to assemble labels.
  • Invalid expression characters or divide-by-zero → empty result, no crash.
  • Target must exist on canvas; unknown target ignored.
Field tokens are block IDs ({blockId}), not display labels. Use the Value field picker or the Formula inserter so IDs stay correct.

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What changes on fill

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Configure in Studio

1

Add or pick target field

Integer, currency, rating, Calculated block, etc. — set result type (number vs text) in block settings when relevant.
2

Add Calculated block OR Then → Calculate

Calculated blocks ship with When Always → Calculate; other rules add Calculate manually.
3

Select target

Pick from the list of Calculated (Σ) and number fields on the form — you do not type a field name. Add a Calculated block first if the list is empty.
4

Choose an operation

Add, Subtract, Multiply, Divide, Assign, or Formula.
  • Assign — set the target to a number or another field’s answer.
  • Add / Subtract / Multiply / Divide — apply that op using a number or another field (same Value control).
  • Formula — opens Edit formula. Type math, click + − × ÷ ( ), or type @ to mention only supported fields (numbers, ratings, choices, calculated).
5

Set Value

One control: type a literal or open the dropdown and pick an input field. No separate “Answer of…” / “Insert field…” for simple ops.
6

Choose number vs text on target

Number mode evaluates math; text mode concatenates only (use Formula for templates).
7

Add downstream When (optional)

Separate rule reading calculated field — e.g. When Total greater than 1000.
8

Test on Fill

Change inputs — watch target update live.

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Worked examples

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Order total (Formula)

When Always → Calculate Order total Formula {quantity} * {unit_price}

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Add a surcharge

When Plan equals Pro → Calculate Final price Multiply 1.2
(or Formula {base_price} * 1.2)

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Assign from another field

When Use company address checked → Calculate Shipping city Assign (pick) Billing city

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Quiz score (Add points)

Calculated Σ Score = 0 on the canvas.
When Q1 is (correct) → Calculate Σ Score Add 10
When Q2 is (correct) → Calculate Σ Score Add 10
Then: When Score ≥ 70 → Jump to page Pass.

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Quiz score (Formula sum)

When Always → Calculate Score Formula {q1} + {q2} + {q3}
(when each question already stores a numeric point value)

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Personalized greeting (Formula, text)

When Always → Calculate Heading Formula Thanks, {first_name}!

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Test on fill

1

Fill all numeric tokens

Target shows expected result.
2

Clear one token

Number result empties — not partial math with zero substitution.
3

Text mode with missing name

Template shows with blank where token was.
4

Downstream When on calculated field

Fires in same recalc pass after Calculate runs (rule order matters on board).
5

Conditional Calculate

Formula updates only when When true for that rule.

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Common mistakes

  • Typing field labels instead of picking fields or inserting {blockId} tokens.
  • Expecting math in text result type.
  • Referencing later-page fields before answered — blank tokens empty numeric result.
  • Removing Always from Calculated block without replacement trigger.

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Troubleshooting

Wrong token ids, blank inputs in number mode, or invalid characters in expression.
Check operator precedence — use parentheses in Formula. Verify Value points to the intended field.
Place Calculate rule before When-on-target in Logic Board order.
Target in text mode but tokens malformed — pick fields from Value / Formula inserter, not hand-typed braces with labels.
Last modified on September 7, 2026