Bug: Cannot add formulas in the shipping cost field

[tiago-123]

Prerequisites

• I have carried out troubleshooting steps and I believe I have found a bug.
• I have searched for similar bugs in both open and closed issues and cannot find a duplicate.

Describe the bug

After updating WooCommerce to the latest version 10.1.0, I have encountered an issue while trying to configure or update shipping rules in both new and old WooCommerce installations.

The issue appears to be related to adding formulas in the cost field. When I try to add a formula, the field validation displays an error message “Please enter a valid number” and the save button becomes disabled.

Expected behavior

The expected behavior would be able to enter a formula such as 5 + [cost] or 2 * [qty].

Actual behavior

When I try to add a formula, the field validation displays an error message “Please enter a valid number” and the save button becomes disabled.

Steps to reproduce

1. Go to shipping settings
2. Add a new shipping method
3. Choose flat rate
4. Try adding a formula in the shipping cost field

WordPress Environment

System Status Report

### WordPress Environment ###

WordPress address (URL): [Redacted]
Site address (URL): [Redacted]
WC Version: 10.1.0
Legacy REST API Package Version: O plugin Legacy REST API não está instalado neste site.
Action Scheduler Version: ✔ 3.9.3
Log Directory Writable: ✔
WP Version: 6.8.2
WP Multisite: –
WP Memory Limit: 512 MB
WP Debug Mode: –
WP Cron: ✔
Language: pt_BR
External object cache: ✔

### Server Environment ###

Server Info: LiteSpeed
Server Architecture: Linux 5.14.0-503.34.1.el9_5.x86_64 x86_64
PHP Version: 8.4.4
PHP Post Max Size: 256 MB
PHP Time Limit: 300
PHP Max Input Vars: 5000
cURL Version: 7.76.1
OpenSSL/3.2.2

SUHOSIN Installed: –
MySQL Version: 10.11.10-MariaDB-log
Max Upload Size: 256 MB
Default Timezone is UTC: ✔
fsockopen/cURL: ✔
SoapClient: ✔
DOMDocument: ✔
GZip: ✔
Multibyte String: ✔
Remote Post: ✔
Remote Get: ✔

### Database ###

[REDACTED]

### Post Type Counts ###

attachment: 23
customize_changeset: 4
page: 8
post: 2
product: 5
product_variation: 5
revision: 18
rm_content_editor: 1
shop_coupon: 2
shop_order_placehold: 8
wp_font_face: 36
wp_font_family: 12
wp_global_styles: 1
wp_navigation: 1

### Security ###

Secure connection (HTTPS): ✔
Hide errors from visitors: ✔

### Active Plugins (18) ###

Payment Gateway Based Fees and Discounts for WooCommerce: por Tyche Softwares – 2.17.0
Code Snippets: por Code Snippets Pro – 3.6.8
Facebook para WooCommerce: por Facebook – 3.5.5
FluentSMTP: por Equipe FluentSMTP & WPManageNinja – 2.2.90
Google for WooCommerce: por WooCommerce – 3.3.1
Site Kit por Google: por Google – 1.159.0
IA Hostinger: por Hostinger – 3.0.0
Hostinger Integração Fácil: por Hostinger – 2.0.86
Alcance do Hostinger: por Hostinger – 1.0.2
Hostinger Tools: por Hostinger – 3.0.47
LiteSpeed Cache: por LiteSpeed Technologies – 7.3.0.1
PagBank for WooCommerce: por PagBank – 1.2.4
Pinterest para WooCommerce: por WooCommerce – 1.4.21
Rank Math SEO: por Rank Math SEO – 1.0.251
Calculadora de Frete para o Brasil: por Link Nacional – 4.3.2
WooCommerce Cart Abandonment Recovery: por Brainstorm Force – 1.3.3
Brazilian Market on WooCommerce: por Claudio Sanches – 4.0.2
WooCommerce: por Automattic – 10.1.0

### Inactive Plugins (0) ###


### Dropin Plugins () ###

object-cache.php: LiteSpeed Cache - Object Cache (Drop-in)

### Must Use Plugins (2) ###

Hostinger Preview Domain: por Hostinger – 1.3.4
Hostinger Smart Auto Updates: por Hostinger – 1.0.7

### Settings ###

Legacy API Enabled: –
Force SSL: –
Currency: BRL (R$)
Currency Position: left_space
Thousand Separator: .
Decimal Separator: ,
Number of Decimals: 2
Taxonomies: Product Types: external (external)
grouped (grouped)
simple (simple)
variable (variable)

Taxonomies: Product Visibility: exclude-from-catalog (exclude-from-catalog)
exclude-from-search (exclude-from-search)
featured (featured)
outofstock (outofstock)
rated-1 (rated-1)
rated-2 (rated-2)
rated-3 (rated-3)
rated-4 (rated-4)
rated-5 (rated-5)

Connected to WooCommerce.com: –
Enforce Approved Product Download Directories: ✔
HPOS feature enabled: ✔
Order datastore: Automattic\WooCommerce\Internal\DataStores\Orders\OrdersTableDataStore
HPOS data sync enabled: –
Enabled Features: analytics
marketplace
order_attribution
site_visibility_badge
remote_logging
email_improvements
blueprint
custom_order_tables


### Logging ###

Enabled: ✔
Handler: Automattic\WooCommerce\Internal\Admin\Logging\LogHandlerFileV2
Retention period: 30 dias
Level threshold: –
Log directory size: 207 KB

### WC Pages ###

Base da loja: #6 - /
Carrinho: #7 - /carrinho/ -  Contém o bloco woocommerce/classic-shortcode
Finalização de compra: #8 - /checkout/ -  Contém o bloco woocommerce/classic-shortcode
Minha conta: #9 - /minha-conta/ -  Contém o shortcode [woocommerce_my_account]
Termos e condições: #88 - /termos-de-uso/

### Theme ###

Name: Ecommerce WP Theme
Version: 1.0
Author URL: 
Child Theme: ❌ – Recomendamos você utilizar um tema filho no caso de você estiver personalizando o WooCommerce em um tema ascendente. Veja como criar um tema filho
Theme type: Tema clássico
WooCommerce Support: ✔

### Templates ###

Overrides: ecommerce-wp-theme/woocommerce/archive-product.php
ecommerce-wp-theme/woocommerce/cart/cart-empty.php
ecommerce-wp-theme/woocommerce/cart/cart-shipping.php
ecommerce-wp-theme/woocommerce/cart/cart-totals.php
ecommerce-wp-theme/woocommerce/cart/cart.php versão 7.9.0 está desatualizado. A versão do core é 10.1.0
ecommerce-wp-theme/woocommerce/cart/mini-cart.php versão 9.4.0 está desatualizado. A versão do core é 10.0.0
ecommerce-wp-theme/woocommerce/cart/proceed-to-checkout-button.php
ecommerce-wp-theme/woocommerce/cart/shipping-calculator.php
ecommerce-wp-theme/woocommerce/checkout/cart-errors.php
ecommerce-wp-theme/woocommerce/checkout/form-billing.php
ecommerce-wp-theme/woocommerce/checkout/form-checkout.php
ecommerce-wp-theme/woocommerce/checkout/form-login.php versão 3.8.0 está desatualizado. A versão do core é 10.0.0
ecommerce-wp-theme/woocommerce/checkout/form-pay.php
ecommerce-wp-theme/woocommerce/checkout/form-shipping.php
ecommerce-wp-theme/woocommerce/checkout/form-verify-email.php
ecommerce-wp-theme/woocommerce/checkout/payment-method.php
ecommerce-wp-theme/woocommerce/checkout/payment.php
ecommerce-wp-theme/woocommerce/checkout/review-order.php
ecommerce-wp-theme/woocommerce/checkout/terms.php
ecommerce-wp-theme/woocommerce/checkout/thankyou.php
ecommerce-wp-theme/woocommerce/content-product.php
ecommerce-wp-theme/woocommerce/content-single-product.php
ecommerce-wp-theme/woocommerce/content-widget-price-filter.php
ecommerce-wp-theme/woocommerce/global/breadcrumb.php
ecommerce-wp-theme/woocommerce/global/form-login.php
ecommerce-wp-theme/woocommerce/global/quantity-input.php versão 9.4.0 está desatualizado. A versão do core é 10.1.0
ecommerce-wp-theme/woocommerce/loop/no-products-found.php
ecommerce-wp-theme/woocommerce/loop/orderby.php
ecommerce-wp-theme/woocommerce/loop/pagination.php
ecommerce-wp-theme/woocommerce/loop/price.php
ecommerce-wp-theme/woocommerce/myaccount/dashboard.php
ecommerce-wp-theme/woocommerce/myaccount/form-edit-account.php
ecommerce-wp-theme/woocommerce/myaccount/form-edit-address.php
ecommerce-wp-theme/woocommerce/myaccount/form-login.php versão 9.7.0 está desatualizado. A versão do core é 9.9.0
ecommerce-wp-theme/woocommerce/myaccount/form-lost-password.php
ecommerce-wp-theme/woocommerce/myaccount/form-reset-password.php
ecommerce-wp-theme/woocommerce/myaccount/lost-password-confirmation.php
ecommerce-wp-theme/woocommerce/myaccount/my-account.php
ecommerce-wp-theme/woocommerce/myaccount/my-address.php
ecommerce-wp-theme/woocommerce/myaccount/navigation.php
ecommerce-wp-theme/woocommerce/myaccount/orders.php
ecommerce-wp-theme/woocommerce/myaccount/view-order.php versão 3.0.0 está desatualizado. A versão do core é 10.1.0
ecommerce-wp-theme/woocommerce/notices/error.php
ecommerce-wp-theme/woocommerce/notices/notice.php
ecommerce-wp-theme/woocommerce/notices/success.php
ecommerce-wp-theme/woocommerce/product-searchform.php
ecommerce-wp-theme/woocommerce/single-product/add-to-cart/variable.php
ecommerce-wp-theme/woocommerce/single-product/add-to-cart/variation-add-to-cart-button.php
ecommerce-wp-theme/woocommerce/single-product/price.php
ecommerce-wp-theme/woocommerce/single-product/product-attributes.php
ecommerce-wp-theme/woocommerce/single-product/product-thumbnails.php
ecommerce-wp-theme/woocommerce/single-product/related.php
ecommerce-wp-theme/woocommerce/single-product/share.php
ecommerce-wp-theme/woocommerce/single-product/tabs/description.php
ecommerce-wp-theme/woocommerce/single-product/tabs/tabs.php
ecommerce-wp-theme/woocommerce/single-product.php

Outdated Templates: ❌
					
					
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### Admin ###

Enabled Features: activity-panels
analytics
product-block-editor
coupons
core-profiler
customize-store
customer-effort-score-tracks
import-products-task
experimental-fashion-sample-products
shipping-smart-defaults
shipping-setting-tour
homescreen
marketing
mobile-app-banner
onboarding
onboarding-tasks
pattern-toolkit-full-composability
product-custom-fields
remote-inbox-notifications
remote-free-extensions
payment-gateway-suggestions
printful
shipping-label-banner
subscriptions
store-alerts
transient-notices
woo-mobile-welcome
wc-pay-promotion
wc-pay-welcome-page
launch-your-store
add-to-cart-with-options-stepper-layout

Disabled Features: product-data-views
experimental-blocks
experimental-iapi-mini-cart
experimental-iapi-runtime
coming-soon-newsletter-template
minified-js
product-pre-publish-modal
settings
async-product-editor-category-field
product-editor-template-system
use-wp-horizon
experimental-wc-rest-api

Daily Cron: ✔ Next scheduled: 2025-08-14 02:40:58 -03:00
Options: ✔
Notes: 53
Onboarding: completed

### Action Scheduler ###

Canceled: 2
Oldest: 2025-07-18 02:38:42 -0300
Newest: 2025-08-13 16:16:57 -0300

Complete: 1.577
Oldest: 2025-07-17 23:42:06 -0300
Newest: 2025-08-13 17:01:14 -0300

Failed: 4
Oldest: 2025-07-18 02:57:20 -0300
Newest: 2025-08-13 03:05:30 -0300

Pending: 19
Oldest: 2025-08-13 17:07:15 -0300
Newest: 2025-08-19 14:57:09 -0300


### Status report information ###

Generated at: 2025-08-13 17:03:04 -03:00

Isolating the problem

• I have deactivated other plugins and confirmed this bug occurs when only WooCommerce plugin is active.
• This bug happens with a default WordPress theme active, or Storefront.
• I can reproduce this bug consistently using the steps above.

[LovingBrother]

Had a forum thread here: https://wordpress.org/support/topic/cannot-add-formulas-in-the-shipping-cost-field/#post-18598222
I tested on my test site, and I can confirm that this is a bug in the latest 10.1.0 version.
Rolling back to 10.0.4 resolved the issue.

[nerrad]

Hi there, thanks for the report, this is a duplicate of #60334 and a fix is being worked on in this PR (#60348).