How to build a conditional logic form

A conditional logic form changes what it asks based on earlier answers, so each person only sees the questions that apply to them. In big you build one visually: split the form into pages, add fork rules at the end of a page to send people to different pages depending on what they answered, and add visibility conditions to individual questions that should only appear for some people. There's nothing to write, and you can test every path before you share the link.

What you need

• A big workspace.
• A rough map of your form: which answer should send someone where. Five minutes with a pen saves a lot of rearranging later.
• Nothing on Instagram. Forms work without a connected account.

If the form already exists in Typeform, you can import it under Forms → Import rather than rebuilding it, then add the logic in big

Step 1: Choose question types you can branch on

This is the step people skip, and it decides everything after it. A question's type controls which comparisons a rule can make:

So if a question is going to decide where someone goes, make it a single choice or dropdown rather than multiple choice. A rating works well for "at most 3 → ask what went wrong". Field types covers each type's validation.

Step 2: Split the form into pages

Open Forms, click New form, give it a title, and add your first questions. Then use + Add page at the top of the canvas to add pages. Put each group of questions that only some people should see on its own page.

Branching happens between pages, so the question that decides the route must sit on an earlier page than the questions it controls. A form can have up to 20 pages and 100 fields.

Step 3: Add fork rules

Open a page in the editor and find After this page. Each rule reads "if the answer to X is …, go to page Y". When someone finishes the page, big checks the rules in order (rule 1, rule 2, and so on) and the first match decides where they go.

• A rule can point at any other page, earlier or later, or straight to submit to end the form early.
• Everyone else is where people go when no rule matches. Left alone, that's the next page, or submit on the last page.
• + A new page in the destination list creates a page and points the rule at it in one go. That's how you branch from page 1 of a brand new form.
• Loops won't save. A route that could send someone round in circles is rejected.

A page can hold up to 10 fork rules. Conditional logic has the full rules.

Step 4: Show single questions only when they apply

Sometimes a whole page is too much and you only want one extra question. Open that question and tick Only show this question when…, then pick an earlier answer. If it doesn't match, the question is skipped and nothing is recorded for it.

The condition has to point at a question on a previous page, never the same page or a later one. That's why the option doesn't appear on page 1.

A worked example

Say you're screening collaborators:

1. Page 1 asks "Are you a brand or a creator?" as a single choice.
2. A fork rule on page 1 sends brand to page 2 (budget questions). Everyone else goes to page 3 (portfolio questions).
3. Page 2's everyone else goes straight to submit, so brands skip the creator questions.

One form, two experiences, and nobody answers a question that wasn't meant for them.

Check it worked

Play-test the form in the builder and walk through every path, choosing different answers each time. Play-testing records nothing, so your stats stay clean. Then set the form's status to active and open the public /f/ link on your phone to try it as a respondent would. Forms with pages or logic step through in the browser, so they need JavaScript turned on.

Once real responses arrive, Form stats shows drop-off per page. Each page is measured against the people who actually reached it, so someone your logic routed past a page isn't counted as dropping off.

If it does not work

• The question you want isn't in the rule's picker. Its type can't be tested, most often because it's multiple choice. Change the type or ask a single-choice question instead.
• A rule never fires. A rule missing its question, its answer or its destination routes nobody, and the editor says so under the rule. Also check the order: an earlier rule that matches wins.
• A page says "not reached yet". Nothing leads to it. Point a fork rule or an earlier page's everyone else at it.
• The form won't save. Look for a loop, where one page sends people back to a page that leads to it again.

Where to go next

Once the form is live, put it on your link page with a form block and see How to track link in bio clicks to measure what reaches it. The form's thank-you screen can send people on to that link page too, which the forms guide explains under the confirmation screen.