Smart Booking

Smart Booking is a completely free WordPress booking plugin built specifically for consultation-style appointments tied to a person (a staff member). It is designed for use cases such as lawyers, certified professionals, marriage agencies, chiropractic clinics, and tutoring schools.

Key Features

• Completely free, no limits — There is no Pro version, no paid add-ons, and no license activation. Every feature is free.
• Ready in 5 minutes — Activating the plugin auto-creates a default store, staff member, and the three core fields (name, email, phone). Just paste the [smart_booking] shortcode into a post or page to display the booking form.
• Optimized for the Japanese booking flow — A 3-step flow (“input → confirmation → done”) that lets the customer review their entries on a dedicated confirmation screen before finalizing the booking.
• Multi-store / multi-staff management — Manage schedules per store and per staff member. Whether customers see the store-select and staff-select steps is set with two switches on the “Settings > Basic Settings” tab (both off by default). When a step is hidden, the first store in the list is selected automatically, and an available staff member is assigned automatically in list order.
• Flexible schedule configuration — Time slots in 30 / 60 / 90 / 120-minute units, capacity per slot, weekday-pattern bulk copy, and an option to overwrite existing schedules.
• Calendar display modes — Choose between day view (horizontal scroll), month view (calendar grid), or a toggle between both, configurable from the admin screen.
• Custom fields — In addition to the three built-in fields (name, email, phone), administrators can add text, email, phone, textarea, select, radio, and checkbox fields.
• Email notifications — Automatic emails are sent to the customer and the administrator when a booking is received, and a confirmation email is sent to the customer on approval. All templates are editable from the admin screen.
• Design customization — Button color, date-selection color, time-slot color, required-mark color, and focus color are all configurable from the admin screen.
• Concurrent booking protection — Capacity is enforced through a single atomic SQL UPDATE, preventing double-bookings when multiple users submit at the same moment.
• Google Tag Manager (GTM) integration — The booking form always pushes events to window.dataLayer, with no setup required in the plugin: smart_booking_step each time a step is displayed (the booking_step key holds store_select, staff_select, date_select, time_select, form_input, or confirm), and smart_booking_complete (with booking_step set to complete) once when a booking is completed. Use smart_booking_complete as a Custom Event trigger in GTM to fire GA4 or Google Ads conversion tags. Skipped steps are not pushed, and steps displayed again (for example after returning from the confirmation screen) are pushed again. The GTM container tag itself must be installed separately on your site.
• WordPress.org guideline compliant — No external CDN scripts/styles, no PHP sessions, all queries use $wpdb->prepare(), all output is escaped, and every REST endpoint enforces nonce + current_user_can('manage_options').

Supported booking flow

[Store Select] → [Staff Select] → [Date Select] → [Time Select] → [Form Input] → [Confirmation] → [Done]

The store-select and staff-select steps are shown only when they are turned on with the switches on the “Settings > Basic Settings” tab. Both are off by default, so the customer starts directly from date selection. When turned on, a step is shown even if there is only one store or one staff member. A form that specifies a store with the shortcode’s store_id attribute never shows the store-select step.

Optional integrations (off by default)

The following external integrations are off by default. They only initiate any outbound traffic after an administrator explicitly enables them on the “Integrations” tab and provides the required credentials (API key, etc.).

• Google Calendar integration — Creates a calendar event when a booking is received and deletes it on cancellation.
• ChatWork notifications — Posts a notification message to a designated ChatWork room when a booking is received.

See the “External services” section below for full details.

Customization & feature requests

For feature requests and customization inquiries, please contact the developer, Liberdade Inc., or visit our service site at wp-smart-booking.com.

Source code

The complete source code, including the un-minified JavaScript and CSS sources under src/, is publicly available on GitHub:

https://github.com/KeisukeYokoyama/SmartBooking

External services

This plugin may communicate with the following external services. In every case, outbound communication happens only after the site administrator has explicitly enabled and configured the feature. Google Calendar integration and ChatWork notifications are off by default and must be enabled on the “Settings > Integrations” tab. The postal code lookup only runs if the administrator adds an “Address” field to a form.

Google Calendar API

• Endpoint: https://www.googleapis.com/calendar/v3/
• Purpose: Creates a Google Calendar event when a booking is received, and deletes the event when the booking is cancelled.
• Data sent: Booking date and time, customer name, store name, staff name, reservation number.
• When: On booking reception (event creation) and on cancellation (event deletion).
• Authentication: Service account JSON key, uploaded by the administrator on the settings screen.
• Default: Off
• Terms of service: Google APIs Terms of Service
• Privacy policy: Google Privacy Policy

ChatWork API

• Endpoint: https://api.chatwork.com/v2/
• Purpose: Posts a notification message to a designated ChatWork room when a booking is received.
• Data sent: Customer name, booking date and time, store name, staff name, reservation number.
• When: Immediately after the customer submits the booking form.
• Authentication: API token, entered by the administrator on the settings screen.
• Default: Off
• Terms of service: ChatWork Terms of Service
• Privacy policy: ChatWork Privacy Policy

Postal code lookup API (zipcloud)

• Endpoint: https://zipcloud.ibsnet.co.jp/api/search
• Purpose: Auto-completes the address (prefecture, city, town) from a postal code entered in the “Address” field of the booking form.
• Data sent: Only the postal code that was entered. No personally identifiable information is sent.
• When: When a customer enters a 7-digit postal code, provided the administrator has added an “Address” field to the form and postal code auto-completion is enabled (the default).
• Default: No communication occurs at all unless an “Address” field is added.
• Terms of service: zipcloud API terms of use

If none of these integrations are enabled and configured, Smart Booking does not communicate with any external service.