Kimai — Self-Hosted Open Source Time Tracking

Introduction

Kimai is a free, open-source time-tracking application designed for freelancers, agencies, and teams. It lets you track working hours against projects and activities, generate invoices, and produce detailed reports. Being self-hosted, all time and billing data stays under your control.

What Kimai Does

• Tracks time entries with start/stop timers or manual duration entry
• Organizes work by customers, projects, and activities in a hierarchical structure
• Generates invoices from tracked time using customizable templates
• Produces reports and exports in PDF, CSV, and Excel formats
• Supports multi-user teams with role-based permissions and approval workflows

Architecture Overview

Kimai is built on Symfony (PHP) with a MySQL or MariaDB backend. The frontend uses server-rendered templates with some JavaScript enhancements for the timer and calendar views. A REST API provides full access to all entities for integrations. The plugin system extends functionality through Symfony bundles.

Self-Hosting & Configuration

• Deploy with Docker using the official kimai/kimai2 image with a database volume
• Alternatively install on any PHP 8.1+ host with Composer and a MySQL/MariaDB database
• Configure database connection, mailer DSN, and app secret in the .env file
• Create the first admin user via bin/console kimai:user:create admin admin@example.com ROLE_SUPER_ADMIN
• Use a reverse proxy for HTTPS and optionally configure LDAP or SAML for enterprise SSO

Key Features

• One-click timer with running stopwatch and support for multiple simultaneous timers
• Invoice generation with customizable templates in DOCX, ODS, and HTML formats
• Detailed reporting with filters by date range, customer, project, user, and activity
• Plugin marketplace with extensions for vacation tracking, task management, and expenses
• REST API for integrating with project management tools, calendars, and billing systems

Comparison with Similar Tools

• Toggl Track — polished SaaS with team features; Kimai is self-hosted and free for unlimited users
• Clockify — free tier with cloud hosting; Kimai gives full data ownership and invoicing built in
• Harvest — invoicing and time tracking SaaS; Kimai offers similar features without recurring costs
• Traggo — simpler Go-based time tracker; Kimai provides richer reporting and invoicing

FAQ

Q: Is Kimai free for teams? A: Yes. The open-source edition supports unlimited users and projects at no cost. You only pay if you want commercial plugins or support.

Q: Can I generate invoices from tracked time? A: Yes. Kimai includes a built-in invoice engine with customizable templates. Select time entries, choose a template, and export as PDF, DOCX, or other formats.

Q: Does Kimai integrate with project management tools? A: The REST API allows integration with tools like Jira, Trello, and custom dashboards. Community plugins provide additional connectors.

Q: What authentication methods are supported? A: Local accounts, LDAP, SAML, and custom authentication via Symfony security bundles.

Sources

• https://github.com/kimai/kimai
• https://www.kimai.org/documentation/