solidtime is a modern open-source time tracking application designed for freelancers and agencies. It features project, task, and client management, billable rates, multi-organization support, and data import from other tracking apps. It offers self-hosting and is licensed under AGPL-3.0.

Titra is a self-hosted, open-source time tracking and project management tool for freelancers and small teams. It enables users to track time, manage projects and tasks, and generate detailed reports and graphs.

django-timepiece is a multi-user, open source application for tracking employee time on projects. It provides features such as time sheets, project and business management, dashboards, payroll reporting, and invoicing, making it directly relevant for time tracking needs.

Easy Redmine is an open-source project management and time-tracking tool that extends Redmine, supporting Agile and Waterfall methodologies, risk/resource management, and integration with various platforms. It is suitable for teams seeking customizable and scalable time-tracking solutions.

Group-Office is a web-based groupware and CRM platform with built-in time tracking, time-based reporting, timesheets, project budgeting, and invoicing, ideal for organizations managing multiple projects and clients.

aitrack.work is a minimal, open-source self-hosted task-based time tracker for everyday use, enabling users to organize and monitor time spent on tasks.