If you sell anything priced by weight or volume, groceries, cosmetics, hardware, paint, bulk foods, showing a price per unit next to the regular price matters more than it used to. In parts of the EU it is a legal requirement under unit pricing rules like Germany’s PAngV, and even where it isn’t required, a visible “$4.99 / kg” builds the kind of trust that gets a cart completed instead of abandoned for a competitor’s listing. WooCommerce has no built in way to do this. Four plugins handle price per unit differently, and one of them, despite sharing almost the exact same name as another, solves a completely different problem. This post compares all four and tells you which one to install.
| Plugin | Best For | Price | Last Updated |
|---|---|---|---|
| Unit Of Measure (UOM) for WooCommerce | A plain text label after the price, no math | Free | September 2026 |
| Price Per Unit for WooCommerce | Auto-calculated price per kg or liter from the weight field | Free, Pro from $30/year | August 2025 |
| Flexible Quantity & Price Calculator for WooCommerce | Letting customers actually buy by weight, area, or volume | Free, Pro from €79/year | October 2026 |
| Unit Price for WooCommerce (Condless) | Selling by the unit but pricing by actual weight after weighing (butchers, fishmongers) | Free | August 2026 |
Unit Of Measure (UOM) for WooCommerce
Unit Of Measure (UOM) for WooCommerce does exactly one thing: it adds a text field to each product where you type whatever should appear after the price, “/kg,” “/liter,” “per dozen,” and it gets stitched onto the price display. There’s no calculation happening anywhere in this plugin.
- Price: Free
- Requires: WordPress 6.5+, PHP 7.4+
- Last updated: September 2026
Setup is as simple as the plugin itself. Open a product, go to the Inventory tab in the product data panel, and type your unit text into the new field that appears there. Publish or update the product and the text shows up next to the price on the front end. That’s the entire workflow, repeated per product.
The honest limitation is that it’s a label, not a calculation. If your price changes but you forget to update the unit text, the two will drift out of sync, and because it’s set per product with no global default or bulk editor, a catalog of a few hundred SKUs means a few hundred manual edits. If you only have a handful of products that need this, or you want full control over the exact wording, it’s the lightest option on this list by a wide margin. If you need the plugin to do the division for you, keep reading.
Price Per Unit for WooCommerce
Price Per Unit for WooCommerce by mechcomp.cz takes the product’s regular price and divides it by the weight you’ve already entered for shipping, then displays the result as a recalculated unit price. This is the plugin most stores searching for “price per unit in WooCommerce” actually want: set the weight once, and the unit price updates itself whenever the regular price changes.
- Price: Free, Pro from $30/year
- Requires: WordPress 4.4+, PHP 7.2+
- Last updated: August 2025
Setup has two layers. Store-wide defaults live under WooCommerce > Settings > Products > Price Per Unit, where you turn the feature on and set a recalculation ratio: enter 1 to show a price per kilogram, or 0.1 if your prices are in kilograms but you want to display per 100 grams. Per-product overrides live in a Price Per Unit tab inside the product editor, which takes priority over the store-wide setting. The plugin only works once a product has a weight entered under its Shipping tab (Products > a product > Shipping > Weight), and for variable products that means setting weight per variation.
You can choose whether the recalculated price replaces the regular price or appears as a second line beneath it, and append your own suffix like “/kg.”
The free version applies one set of rules across the whole catalog by default, so running a mixed shop where some items sell by the kilogram and others by the piece takes some per-product configuration to get right, and the Pro upgrade exists mainly to make variation pricing and per-product overrides less fiddly. The plugin’s own documentation also still lists compatibility only up to WooCommerce 4.0.x, a readme detail that hasn’t been refreshed even though the plugin itself was last updated in August 2025, now well over a year ago. It still works on current WooCommerce in practice, but that’s a maintenance signal worth noticing before you lean on it for a compliance requirement.
Flexible Quantity & Price Calculator for WooCommerce
Flexible Quantity & Price Calculator for WooCommerce by WP Desk is a different kind of tool. Instead of just labeling or recalculating a static price, it lets the shopper pick their own quantity in weight, dimension, area, or volume units, and the displayed price recalculates live on the product page as they adjust it, the same interaction pattern as buying fabric by the meter or paint by the liter at a hardware store.
- Price: Free, Pro from €79/year
- Requires: WordPress 6.4+, PHP 7.4+
- Last updated: October 2026
To set it up, open a product, go to the Product Data section, and click the Flexible Quantity tab that the plugin adds. Enable the calculator for that product, pick a unit type (weight in g/kg/t/oz/lbs/tn, dimension, area, or volume), set the price per unit and the increment the quantity should move by, then optionally cap it with a minimum and maximum. The free version ships with that fixed list of unit types; custom units are a Pro-only feature.
This is the most capable plugin on the list, but it’s also doing more than a lot of stores actually need. If the goal is purely to show “$4.99 / kg” next to a fixed price, this plugin changes how the product is purchased rather than just how it’s labeled, which is more setup and more for the customer to interact with than the job calls for. It earns its place when you genuinely want customers buying 1.25 kg of something instead of a flat 1 unit, not when you just want a compliant price label.
Unit Price for WooCommerce (Condless)
Unit Price for WooCommerce by Condless is the one to read carefully before installing, because its name makes it sound like a direct competitor to the plugin above, and it solves a genuinely different problem. It’s built for products sold by the unit but priced by weight that isn’t known until the item is physically weighed, the classic fish counter or butcher shop scenario.
- Price: Free
- Requires: WordPress 5.2+, PHP 7.0+
- Last updated: August 2026
Setup: in the plugin’s settings, enable the Quantity Units option, then on each product set the price of one unit in the regular price field, the approximate weight of one unit in the Shipping tab’s weight field, and select “Weight” as that product’s Quantity Unit. When a customer orders one salmon configured at an estimated 3 kg, the order quantity is automatically recalculated from 1 to 3 at checkout. After the fish is actually weighed and comes in at 3.2 kg, the shop owner edits the order quantity to 3.2 and the total updates to match.
The limitation is stated plainly in the plugin’s own documentation: this workflow only makes sense with an authorized or delayed payment method, so the store can charge the correct amount after weighing instead of charging an estimate up front. If your payment gateway doesn’t support delayed capture, this plugin’s core feature doesn’t really work for you, and if what you actually wanted was a simple “price per kg” label on a fixed-price product, Price Per Unit for WooCommerce above is the right plugin, not this one.
How to Pick
- If you just need a label like “/kg” next to a price you update manually and don’t mind the manual upkeep: use Unit Of Measure.
- If you want the unit price calculated automatically from a weight you’ve already entered for shipping, and updated whenever the regular price changes: use Price Per Unit for WooCommerce.
- If you want customers to actually choose their quantity in weight, area, or volume and watch the price change live: use Flexible Quantity & Price Calculator for WooCommerce.
- If your real weight isn’t known until the product is physically weighed after the order is placed, fish, meat, produce sold by the piece: use Unit Price for WooCommerce from Condless, paired with a payment gateway that supports delayed capture.
FAQ
Does WooCommerce show a price per unit natively?
No. WooCommerce core has a weight field for shipping purposes, but it has no setting that turns that weight into a displayed unit price. That calculation, and the display logic around it, is entirely left to plugins.
Is showing a unit price legally required?
It can be, depending on where you sell. Several EU countries, Germany’s PAngV being the best known example, require a visible base price per standard unit (per kg, per liter, and so on) for many packaged goods. Requirements and exact thresholds vary by country, so check your local rules rather than assuming a plugin alone makes you compliant.
Can I show the price per 100 grams instead of per kilogram?
Yes, with Price Per Unit for WooCommerce. Its recalculation ratio setting lets you enter a value like 0.1 to convert a per kilogram price into a per 100 gram display without changing how your prices are actually stored.
Will any of these work on variable products with different weights per variation?
Price Per Unit for WooCommerce supports setting weight per variation, with better variation handling in its Pro version. Flexible Quantity & Price Calculator’s unit settings are configured per simple product; check its documentation before relying on it for a catalog built mostly on variable products.
Sources
- Unit Of Measure (UOM) for WooCommerce, WordPress.org
- Price Per Unit for WooCommerce, WordPress.org
- Price per Unit PRO pricing, mechcomp.cz
- Flexible Quantity & Price Calculator for WooCommerce, WordPress.org
- Flexible Quantity Calculator pricing, WP Desk
- Unit Price for WooCommerce, WordPress.org
- Unit Price for WooCommerce, Condless
None of ConicPlex’s own plugins handle weight-based pricing, so there’s nothing to add to the comparison above honestly. If your store needs something none of these four quite cover, a custom calculation tied to your specific stock units or supplier pricing feed, that’s exactly the kind of build our WordPress plugin development team takes on, and it’s a problem we’ve solved before in custom WooCommerce plugin work for other stores. For broader storefront work beyond pricing display, see our WooCommerce development service and our work with ecommerce clients generally. And if the quantity side of your catalog, rather than the price side, is the real pain point, our piece on setting a minimum and maximum order quantity in WooCommerce covers that specifically.
