Kimai

My recommendation

I recommend Kimai for teams that want to track project time on their own infrastructure. With reports, exports, and invoicing, Kimai covers the path from tracked time to invoice and already offers single sign-on in the open-source version.

Kimai is open-source project time tracking for teams. The software assigns time to customers, projects, and activities and, according to its README, supports reports, exports, and invoicing.

It can be run on-premises or self-hosted and as SaaS. The software is actively maintained and licensed under AGPL v3. It uses PHP, MySQL, and MariaDB.

Fact Sheet

Categories
Status
Actively maintained
License
  • AGPL-3.0
Operation
  • On-Premises / Self-hosted
  • SaaS
Technologies
  • PHP
  • MySQL
  • MariaDB
Single Sign-On (SSO)
MCP server
  • Unknown: not specified

Data last checked on October 27, 2026

Proprietary Add-on Modules

The paid, proprietary module Working hours, vacation, sickness, public holidays extends attendance management with target hours, overtime accounts, vacation, sick leave, public holidays, and monthly approvals. These features are not part of the AGPL core.

The plugin license from Kevin Papst generally allows one production Kimai installation per license and prohibits free redistribution of the plugin. Use as SaaS requires extended license rights. The last version obtained during the subscription may still be used after it ends, while further updates require an active subscription. These terms apply to the add-on module, not to the AGPL core.

Open-Source Alternatives

Match in All Categories

The following products are assigned to the categories «Invoicing» and «Project Time Tracking», just like «Kimai», and match all of them.

Further down, you can find alternatives per category that do not share all categories with «Kimai».

ERPNext

ERPNext combines accounting, quotes, invoices, and time tracking with subscription and contract management in one web application.

  • Accounting
  • Appointment Scheduling
  • Calendar
  • Contracts
  • CRM
  • ERP
  • Invoicing
  • Project Time Tracking

Midday

Midday combines time tracking, invoices, and a financial overview for solo business owners and freelancers.

  • Invoicing
  • Project Time Tracking

Odoo Community

Odoo Community brings together sales, purchasing, inventory, invoicing, calendar, and time tracking in a modular business suite.

  • Calendar
  • CRM
  • Employee Time Tracking
  • ERP
  • Invoicing
  • Project Time Tracking

In the Category «Invoicing»

Akaunting

Akaunting's source-available core manages invoices, income and expenses in the browser. License limits apply to production use.

  • Accounting
  • Invoicing

Aureus ERP

Aureus ERP combines finance, inventory, human resources, customer relationships, and projects through modular apps.

  • Accounting
  • CRM
  • ERP
  • Invoicing
  • Projects

Crater

Crater creates quotes and invoices and manages payments and customer data on your own server.

  • Invoicing

Dolibarr ERP/CRM

Dolibarr combines customer management, quotes, invoices, accounting, and inventory. Modules add management of subscriptions and contracts.

  • Accounting
  • Contracts
  • CRM
  • ERP
  • Invoicing

ERPNext

ERPNext combines accounting, quotes, invoices, and time tracking with subscription and contract management in one web application.

  • Accounting
  • Appointment Scheduling
  • Calendar
  • Contracts
  • CRM
  • ERP
  • Invoicing
  • Project Time Tracking
 My own product

Erdikon

Erdikon creates quotes, invoices, and credit notes with shared master data. QR bills, e-invoices, and payment tracking support invoicing.

  • Invoicing

Invoice Ninja

Invoice Ninja combines quotes and invoices with payment management. You can self-host it or use the hosted service.

  • Invoicing

InvoicePlane

InvoicePlane brings together quotes, invoices, customer data and payments in a self-hostable web app.

  • Invoicing

InvoiceShelf

InvoiceShelf is a self-hostable web app for quotes, invoices, payments, and expenses. The open-source software is built on PHP and Vue.js.

  • Invoicing

LedgerSMB

LedgerSMB manages receivables, payables, and invoices and creates reports for financial accounting.

  • Accounting
  • ERP
  • Invoicing

Midday

Midday combines time tracking, invoices, and a financial overview for solo business owners and freelancers.

  • Invoicing
  • Project Time Tracking

Odoo Community

Odoo Community brings together sales, purchasing, inventory, invoicing, calendar, and time tracking in a modular business suite.

  • Calendar
  • CRM
  • Employee Time Tracking
  • ERP
  • Invoicing
  • Project Time Tracking

SolidInvoice

SolidInvoice creates quotes and invoices and supports online payments for freelancers and small businesses.

  • Invoicing

metasfresh

metasfresh brings together purchasing, sales, warehousing, logistics, production, and finance for companies in trade and manufacturing.

  • Accounting
  • ERP
  • Invoicing

In the Category «Project Time Tracking»

ERPNext

ERPNext combines accounting, quotes, invoices, and time tracking with subscription and contract management in one web application.

  • Accounting
  • Appointment Scheduling
  • Calendar
  • Contracts
  • CRM
  • ERP
  • Invoicing
  • Project Time Tracking

Leantime

Leantime connects project goals with tasks, milestones, and time tracking. Teams plan their work on Kanban boards, among other views.

  • Project Time Tracking
  • Projects

Midday

Midday combines time tracking, invoices, and a financial overview for solo business owners and freelancers.

  • Invoicing
  • Project Time Tracking

Odoo Community

Odoo Community brings together sales, purchasing, inventory, invoicing, calendar, and time tracking in a modular business suite.

  • Calendar
  • CRM
  • Employee Time Tracking
  • ERP
  • Invoicing
  • Project Time Tracking

OpenProject

OpenProject combines task management, Gantt planning, and time tracking. Teams coordinate projects and document their collaboration.

  • Project Time Tracking
  • Projects

OrangeHRM

OrangeHRM Starter manages employee data, leave, working time, job applications, and performance reviews in a self-hostable web application.

  • Employee Time Tracking
  • HR
  • Project Time Tracking

TimeTagger

TimeTagger records working time on an interactive timeline and organizes it with tags. You can self-host it or use it as SaaS.

  • Project Time Tracking

Traggo

Traggo records working time with custom tags and analyzes it in customizable dashboards. The web app runs on your own server.

  • Project Time Tracking