VoxelBooking

VoxelBooking is open-source, self-hosted software for appointments, resource reservations, capacity-based bookings, and classes or events. It is best suited to agencies serving several businesses, owners who control their own infrastructure, and developers comfortable with PHP. The trade-off is clear: you avoid subscription and booking fees, but payment collection and external calendar coordination remain outside the system.

Overview

A single installation can host multiple businesses, with separate booking pages, schedules, staff, customers, and settings for each one. That multi-business structure is useful for an agency managing client accounts without maintaining a separate installation per client. Each responsive public page supports its own colors, logo, and cover image, while an embed widget can place booking on an existing website.

The booking model extends beyond standard appointments to date-range resources, capacity reservations, and events or classes. Administrators receive day and week calendar views, filters, rescheduling and cancellation controls, customer history, and CSV export. Online self-booking, staff calendars, and cancellation controls are included. The breadth makes it adaptable, but businesses needing checkout, deposits, or live availability from other calendars will need separate processes.

Key features

Confirmation, reminder, and cancellation messages are branded and sent through the installation's configured SMTP service. Calendar attachments can be included in emails. Reminder automation depends on a functioning cron job, so deployment is not complete until scheduled tasks and email delivery are correctly maintained.

The booking widget has documented integrations for WordPress, Wix, and Squarespace. A read-only REST API supports reporting and private integrations, but its Agent API cannot create bookings, edit tenants, take payments, or synchronize external calendars. Authenticated keys are limited to 60 requests per minute, which is adequate for modest reporting workloads but a constraint for high-frequency polling.

Data isolation is stated at database level, and bookings stay on the server controlled by the operator. Privacy tooling covers consent collection, privacy-policy links, data-access requests, deletion, and automatic anonymization after a retention period. Deployment requires PHP 8.3 or newer, MySQL 8.0 or newer, email delivery, and cron.

Pricing

The Free plan is unusually unrestricted in product scope: unlimited businesses and no usage-based or seat charges make it suitable for agencies and growing operators that can run their own server. Its real cost is operational rather than subscription-based, because hosting, updates, administration, SMTP, and cron are your responsibility. There is no paid tier to add payment processing, SMS, or calendar synchronization; those capabilities are absent rather than gated behind an upgrade.

Platforms

VoxelBooking is offered as a web application with a self-hosted deployment and an API. The stated server requirements are PHP 8.3 or newer, MySQL 8.0 or newer, email delivery, and cron for reminders. This setup favors users who control hosting or can work with a developer; it is not a turnkey mobile app service.

Who it's for

Freelancers and agencies managing client bookings can use one installation for multiple businesses and embed branded booking pages into client sites. Business owners who want online self-booking without recurring software charges may find the unlimited-business model compelling if they can maintain the server. Developers who prefer working with PHP source code gain an AGPL-3.0 application with its full source available.

It is a poor fit for teams that require appointment payments or deposits, SMS alerts, or automatic Google Calendar and Outlook availability synchronization. Support covers bug reports, installation or usage issues, and feature questions through documentation and GitHub issues; server administration, custom development, and third-party integrations are outside that scope.

Pros and cons

Pros

• No recurring software charge: the Free plan costs nothing with no per-booking or per-seat fees.
• Multi-business structure: one installation separates pages, schedules, staff, customers, and settings for multiple businesses.
• Broad booking model: appointments, date-range resources, capacity reservations, and classes or events fit in the same system.
• Operator-controlled data: tenant isolation and server-side storage support organizations that need infrastructure control.
• Privacy controls: consent, access, deletion, and retention-based anonymization are built into the feature set.

Cons

• No payments or deposits: appointment fees cannot be collected within VoxelBooking.
• No external calendar sync: Google Calendar and Outlook availability must be coordinated elsewhere.
• Self-hosting workload: PHP, MySQL, SMTP, cron, hosting, and maintenance are your responsibility.
• Limited automation API: the read-only Agent API cannot create or modify bookings, and keys are capped at 60 requests per minute.
• No SMS notifications: reminders and cancellations are email-based.

Alternatives

Choose Salon Appointment Scheduling Software for a broader salon-focused shortlist. Appointment Scheduling Software is the better starting point when you want to compare appointment tools generally.

Treatwell Pro suits users wanting Android, iOS, macOS, web, and Windows access with a freemium model; its Advanced plan includes unlimited staff, though marketplace clients can incur a location-dependent commission.

Pronto is a stronger choice for a small, capped operation: its free plan is forever and allows one staff member, 100 clients, and 50 bookings per month, with a $19 a month Starter plan for higher limits.

Salonist offers Android, iOS, and web access, a free marketplace listing with 50 appointments per month, and a $59 a month Essential plan.

TimeTailor is worth choosing when unlimited manual bookings, unlimited staff, reporting, and email reminders are priorities on its free service plan; online booking is a separate $3.90 per conta plan.

NexCal is another self-hosted, free and open-source option with Docker support and zero subscription fees.

Salon Booking System provides a free forever plan for one site with online booking, unlimited services, and email notifications, with a €89 a year Basic plan.

Planity Pro is for businesses seeking a paid Android, iOS, and web suite with agenda and cash-register functions.

Bookido is an alternative freemium booking service with mobile and web platforms.

Verdict

Choose VoxelBooking if you need a flexible, multi-business booking system, control of your data, and genuinely unlimited free usage, and you can operate a PHP/MySQL server. Look elsewhere if collecting appointment payments, sending SMS, or synchronizing Google Calendar and Outlook is central to your workflow.