Water intake calculator template

Free build guide: Water intake calculator for WordPress

This guide rebuilds the Water intake calculator from this site in Gravity Forms: 5 inputs, 6 live results and no submit button. Expect about 33 minutes by hand. The template above is the same form as an import file, and the bundle adds a PDF version of this guide with a screenshot of every setting, plus the stylesheet.

You will end up with:

• Water per day (oz)
• Cups (8 oz)
• Litres
• Water per day (litres)
• Glasses (250 ml)
• Millilitres

What you need

• Gravity Forms (any license) — Calculation fields, radio values and conditional logic are in core.

Everything here is core Gravity Forms. No add-ons.

1. Create the form

1. Go to Forms → New Form and name it Water intake.
2. In Form Settings → Form Layout, set the CSS Class Name to fo-live-only. Step 3 uses it to hide the submit button.
3. Leave the form open in the editor; the fields come next.

2. Add the fields, in this order

Field IDs are assigned as you add fields. If yours come out differently, change the {Label:ID} references in the formulas to match your IDs. Settings not mentioned stay at their defaults.

1. Units · Radio Buttons · ID 1
Custom CSS Class (Appearance tab) fo-segmented.

Choices (tick show values and enter each value):

• lb / oz — value us (selected by default)
• kg / litres — value metric

2. Weight (lb) · Number · ID 2
Number Format 9,999.99; Default Value 160; Conditional Logic (Advanced tab): Show this field if Units is lb / oz..

3. Weight (kg) · Number · ID 3
Number Format 9,999.99; Default Value 73; Conditional Logic (Advanced tab): Show this field if Units is kg / litres..

4. Exercise per day (minutes) · Number · ID 4
Number Format 9,999.99; Default Value 30; Description “Time you actually sweat.”; Layout: half width, on the same row as its neighbour (drag the field beside it in the editor; no CSS class needed).

5. Climate · Radio Buttons · ID 5
Layout: half width, on the same row as its neighbour (drag the field beside it in the editor; no CSS class needed); Custom CSS Class (Appearance tab) fo-segmented.

Choices (tick show values and enter each value):

• Mild — value 0 (selected by default)
• Hot or humid — value 1

6. Water per day (oz) · Number · ID 6
Number Format 9,999.99; Description “From all drinks and about 20% from food. Thirst and pale urine are the real check.”; Custom CSS Class (Appearance tab) fo-result; tick Enable Calculation, Rounding 0; Conditional Logic (Advanced tab): Show this field if Units is lb / oz..

( {Weight lb:2} * 0.5 + {Exercise:4} / 30 * 12 + {Climate:5} * 16 )

7. Cups (8 oz) · Number · ID 7
Number Format 9,999.99; Layout: half width, on the same row as its neighbour (drag the field beside it in the editor; no CSS class needed); Custom CSS Class (Appearance tab) fo-result fo-result--sub; tick Enable Calculation, Rounding 1; Conditional Logic (Advanced tab): Show this field if Units is lb / oz..

( {Weight lb:2} * 0.5 + {Exercise:4} / 30 * 12 + {Climate:5} * 16 ) / 8

8. Litres · Number · ID 8
Number Format 9,999.99; Layout: half width, on the same row as its neighbour (drag the field beside it in the editor; no CSS class needed); Custom CSS Class (Appearance tab) fo-result fo-result--sub; tick Enable Calculation, Rounding 1; Conditional Logic (Advanced tab): Show this field if Units is lb / oz..

( {Weight lb:2} * 0.5 + {Exercise:4} / 30 * 12 + {Climate:5} * 16 ) * 0.0295735

9. Water per day (litres) · Number · ID 9
Number Format 9,999.99; Description “From all drinks and about 20% from food. Thirst and pale urine are the real check.”; Custom CSS Class (Appearance tab) fo-result; tick Enable Calculation, Rounding 1; Conditional Logic (Advanced tab): Show this field if Units is kg / litres..

( {Weight kg:3} * 33 + {Exercise:4} / 30 * 350 + {Climate:5} * 500 ) / 1000

10. Glasses (250 ml) · Number · ID 10
Number Format 9,999.99; Layout: half width, on the same row as its neighbour (drag the field beside it in the editor; no CSS class needed); Custom CSS Class (Appearance tab) fo-result fo-result--sub; tick Enable Calculation, Rounding 1; Conditional Logic (Advanced tab): Show this field if Units is kg / litres..

( {Weight kg:3} * 33 + {Exercise:4} / 30 * 350 + {Climate:5} * 500 ) / 250

11. Millilitres · Number · ID 11
Number Format 9,999.99; Layout: half width, on the same row as its neighbour (drag the field beside it in the editor; no CSS class needed); Custom CSS Class (Appearance tab) fo-result fo-result--sub; tick Enable Calculation, Rounding 0; Conditional Logic (Advanced tab): Show this field if Units is kg / litres..

( {Weight kg:3} * 33 + {Exercise:4} / 30 * 350 + {Climate:5} * 500 )

3. Hide the submit button

The results are live, so nothing needs submitting. Add this filter to your theme’s functions.php or a code-snippets plugin; it hides the button on any form carrying the fo-live-only class:

add_filter( 'gform_submit_button', function ( $button, $form ) {
	return str_contains( (string) rgar( $form, 'cssClass' ), 'fo-live-only' ) ? '' : $button;
}, 10, 2 );

Or with CSS alone: .fo-live-only_wrapper .gform_footer { display: none; }

4. Put it on a page and make it look like this

Add the form to any page with the Gravity Forms block, or the shortcode [gravityform id="X" title="false" ajax="false"]. The form inherits your theme’s styles; the classes you set in step 2 are hooks for the look you see on this site:

• fo-result on a calculation field makes it the big teal result panel.
• fo-result fo-result--sub makes the smaller secondary figures.
• fo-segmented on a radio field turns it into a segmented switch.
• Two fields on one row is the editor’s own column layout: drag a field beside another and the row splits in half. No CSS class is needed, and the old gf_left_half Ready Classes are deprecated.

The bundle includes the two stylesheets that implement those classes, with notes on matching your brand colours. Without them the form still works; it just looks like your theme’s default Gravity Forms styling.

How the maths works is explained under “How it’s calculated” on the live Water intake calculator.