URL Modifications

You can use URL modifications (or URL mods, as we like to call them) to pre-populate fields in your form. Unlike setting predefined values in your form, URL mods pre-populate fields differently for each person that fills out your form. All you have to do is give them a special URL that contains the custom data you want to include in the form.

For example, if you know the name of someone you're sending your form to, you can pre-populate the name field on the form with their name.

Modifying a URL

To use URL mods, modify the end of your form link to include the API ID of the field and custom data you want to pre-populate in that field. To pre-populate multiple fields, separate each field and data combo with an ampersand.

Each field starts with the word "field" immediately followed by the API field number (instructions on how to find it below). The data for the field is up to you!

Form Link: https://subdomain.wufoo.com/forms/form-name/

URL Mod: https://subdomain.wufoo.com/forms/form-name?fieldAPI_ID=data

Example: https://wufoohc.wufoo.com/forms/zn1kdvq07jo69j?field1=Trex&field3=Minmi

If you're using non-alphanumeric characters in your custom data, make sure they're URL encoded.

Finding Your API ID

To find the API ID of your field:

  1. Log in and go to Forms.
  2. Find your form and click More.
  3. Click API Information.
  4. Find the field you want to pre-populate and copy the API ID

URL Mods in Embedded Forms

JavaScript Embed Code

If you're embedding your form with the JavaScript embed code, you can use defaultValues instead of URL mods. In the options section of your code, add the following parameters:


For example:

<div id="wufoo-m7x3w7">
Fill out my <a href="http://username.wufoo.com/forms/m7x3w7">online
<script type="text/javascript">var m7x3w7;(function(d, t) { var s = d.createElement(t), options = { 'userName':'username', 'formHash':'m7x3w7', 'autoResize':true, 'height':'234',
// NOTE: This is the line we are adding to the default snippet.
s.src = ('https:' == d.location.protocol ? 'https://' : 'http://') + 'wufoo.com/scripts/embed/form.js';
s.onload = s.onreadystatechange = function() { var rs = this.readyState; if (rs) if (rs != 'complete') if (rs !=
'loaded') return;
try { m7x3w7 = new
WufooForm();m7x3w7.initialize(options);m7x3w7.display(); } catch (e) {}}; var scr = d.getElementsByTagName(t)[0], par = scr.parentNode; par.insertBefore(s, scr); })(document, 'script');</script>

iFrame Embed Code

If you're embedding your form with the iFrame embed code, you can add your URL mods to the form link within the iFrame code. For example:

<iframe height="260" allowTransparency="true" frameborder="0" scrolling="no" style="width:100%;border:none"
<a href="https://subdomain.wufoo.com/forms/r10w91tr08wiqic/">Fill out my Wufoo form!</a></iframe> 

Wordpress Embed Code

If you're embedding your form with the Wordpress embed code, you can use defaultv instead of URL mods. You can add a parameter like this:


For example:


[wufoo username=”examples” formhash=”z7w4r7232323″ autoresize=”true” height=”517″ header=”show” ssl=”true” defaultv=“Field1=Sally&Field2=Salford”]

URL modifications pre-populate fields differently for each person that fills out your form.

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