License & Deployment Mix: 16 tools – 4 OSS, 12 SaaS. (OSS and SaaS counts can overlap when an open-source tool also offers a vendor-hosted edition.)
What Is Time Tracking / Invoicing?
Time tracking is the systematic recording of hours worked against projects, clients, and tasks for billing, productivity analysis, and resource planning. Invoicing in this context refers to generating client-facing bills from tracked time and expenses. Together, these tools enable professional services firms, MSPs, and freelancers to capture billable work, track utilization, and convert time entries into revenue.
This directory evaluates time tracking and invoicing tools – both self-hosted and SaaS solutions. For Professional Services Automation platforms with built-in time tracking, see PSA / MSP Platforms. For general accounting and invoicing, see ERP & Accounting. For subscription and recurring billing, see Billing / Subscription Management. For project management tools with time tracking features, see proj-mgmt/. For time and attendance (T&A) in the HR context, see Human Resources.
Time Tracking vs Related Systems
| Concern | Time Tracking | PSA | HR T&A | PM |
|---|---|---|---|---|
| Focus | Billable hours | Full services lifecycle | Attendance/PTO | Task progress |
| Billing | Core feature | Core feature | Not typical | Rarely |
| Invoicing | Often included | Always included | No | No |
| Utilization | Core metric | Core metric | Not tracked | Optional |
| Expenses | Often included | Always included | No | Sometimes |
| Payroll | Feeds into | Integrated | Core feature | No |
| Scope | Hours + billing | Quote-to-cash | Clock in/out | Schedules |
Core Capabilities
- Time entry – manual entry, running timers, calendar-based entry, weekly timesheets
- Timer – start/stop clock for real-time tracking; desktop, mobile, and browser extensions
- Project allocation – assign time to specific projects, clients, and tasks
- Billable / non-billable – categorize time as billable to clients or internal overhead
- Expense tracking – capture receipts, mileage, and reimbursable expenses alongside time
- Invoicing – generate invoices from tracked time and expenses; online payment acceptance
- Approval workflows – manager review and approval of submitted timesheets
- Utilization reporting – track billable vs total hours to measure team productivity
- Budgets – set project hour and dollar budgets with alerts on overruns
- GPS / location tracking – verify field worker locations during tracked time; geofencing
Key Concepts
- Billable rate – the per-hour rate charged to a client for tracked time; may vary by employee, project, or task type
- Utilization rate – the ratio of billable hours to total available hours; a key profitability metric for professional services firms
- Timesheet – a periodic (daily/weekly) summary of time entries submitted for approval
- Timer – a running clock that captures elapsed time in real-time; contrasted with manual entry
- Rounding – automatic adjustment of time entries to the nearest increment (e.g., 15-minute blocks) per billing policy
- Cost rate – the internal cost per hour for an employee; compared against billable rate to calculate margin
- WIP (Work in Progress) – unbilled tracked time that has not yet been invoiced; important for cash flow management
- Realization rate – the ratio of invoiced (collected) revenue to total billable value; tracks write-downs and discounts
The information on these pages was researched by a combination of human review and large language models. To suggest an addition or correction, please contact us. Prepared by Rhodium Systems Inc., author of the ResorsIT platform — a unified IT operations management platform for IT teams and MSPs that integrates a curated suite of open-source, commercial, and SaaS applications into a single system with shared identity, single sign-on, access control, and a common audit trail. Use this catalogue only as a starting point for your own research, and review any tool carefully against your own requirements before relying on it. Catalogue data version 2026.197.
Comparison
Deployment Model
| Tool | License | Self-Hosted | SaaS | Docker |
|---|---|---|---|---|
| Kimai | AGPL-3.0 | Yes | No | Yes |
| Invoice Ninja | AAL/AGPL | Yes | Yes | Yes |
| Traggo | GPL-3.0 | Yes | No | Yes |
| Wakapi | MIT | Yes | No | Yes |
| ActivityWatch | MPL-2.0 | Yes | No | No |
| Harvest | Proprietary | No | Yes | N/A |
| Toggl Track | Proprietary | No | Yes | N/A |
| Clockify | Proprietary | No | Yes | N/A |
| Hubstaff | Proprietary | No | Yes | N/A |
| TimeCamp | Proprietary | No | Yes | N/A |
| FreshBooks | Proprietary | No | Yes | N/A |
| Paymo | Proprietary | No | Yes | N/A |
| Replicon | Proprietary | No | Yes | N/A |
| BigTime | Proprietary | No | Yes | N/A |
| QuickBooks Time | Proprietary | No | Yes | N/A |
| Everhour | Proprietary | No | Yes | N/A |
Core Time Tracking Features
| Tool | Timer | Manual | Approvals | Billable | Expenses | GPS | Screenshots |
|---|---|---|---|---|---|---|---|
| Kimai | Yes | Yes | Yes | Yes | Yes | No | No |
| Invoice Ninja | Yes | Yes | No | Yes | Yes | No | No |
| Traggo | Yes | Yes | No | Yes | No | No | No |
| Wakapi | Auto | No | No | No | No | No | No |
| ActivityWatch | Auto | No | No | No | No | No | Yes* |
| Harvest | Yes | Yes | Yes | Yes | Yes | No | No |
| Toggl Track | Yes | Yes | Yes | Yes | No | No | No |
| Clockify | Yes | Yes | Yes | Yes | No | Yes | Yes |
| Hubstaff | Yes | Yes | Yes | Yes | No | Yes | Yes |
| TimeCamp | Auto | Yes | Yes | Yes | No | Yes | Yes |
| FreshBooks | Yes | Yes | Yes | Yes | Yes | No | No |
| Paymo | Yes | Yes | Yes | Yes | Yes | No | No |
| Replicon | Yes | Yes | Yes | Yes | Yes | Yes | No |
| BigTime | Yes | Yes | Yes | Yes | Yes | No | No |
| QuickBooks Time | Yes | Yes | Yes | Yes | No | Yes | No |
| Everhour | Yes | Yes | Yes | Yes | No | No | No |
* ActivityWatch captures window/app screenshots for activity classification, not employee monitoring.
Best time tracking features: Kimai (OSS, full feature set), Harvest and Replicon (commercial, enterprise-grade)
Invoicing Features
| Tool | Invoices | Online Pay | Recurring | Estimates | Multi-Currency |
|---|---|---|---|---|---|
| Kimai | Plugin | No | No | No | Yes |
| Invoice Ninja | Yes | Yes | Yes | Yes | Yes |
| Traggo | No | No | No | No | No |
| Wakapi | No | No | No | No | No |
| ActivityWatch | No | No | No | No | No |
| Harvest | Yes | Yes | No | Yes | Yes |
| Toggl Track | No | No | No | No | No |
| Clockify | Yes | No | No | No | Yes |
| Hubstaff | Yes | Yes | No | No | Yes |
| TimeCamp | Yes | No | No | No | Yes |
| FreshBooks | Yes | Yes | Yes | Yes | Yes |
| Paymo | Yes | Yes | No | Yes | Yes |
| Replicon | Yes | Yes | Yes | Yes | Yes |
| BigTime | Yes | Yes | Yes | Yes | Yes |
| QuickBooks Time | No* | No* | No* | No* | No |
| Everhour | No | No | No | No | No |
* QuickBooks Time relies on QuickBooks Online for invoicing; no native invoice generation.
Best invoicing: Invoice Ninja (OSS, full invoicing suite), FreshBooks and BigTime (commercial, mature)
Project / Task Integration
| Tool | Projects | Tasks | Budgets | PM Integrations |
|---|---|---|---|---|
| Kimai | Yes | Yes | Yes | API only |
| Invoice Ninja | Yes | Yes | No | API only |
| Traggo | Tags | Tags | No | No |
| Wakapi | Yes | No | No | IDE plugins |
| ActivityWatch | No | No | No | No |
| Harvest | Yes | Yes | Yes | Asana, Jira, Trello |
| Toggl Track | Yes | Yes | No | 100+ integrations |
| Clockify | Yes | Yes | Yes | Jira, Asana, Trello |
| Hubstaff | Yes | Yes | Yes | Jira, Asana, Trello |
| TimeCamp | Yes | Yes | Yes | Jira, Asana, Trello |
| FreshBooks | Yes | Yes | Yes | Limited |
| Paymo | Yes | Yes | Yes | Native PM |
| Replicon | Yes | Yes | Yes | Jira, ServiceNow |
| BigTime | Yes | Yes | Yes | Salesforce, Jira |
| QuickBooks Time | Yes | Yes | Yes | QuickBooks, Jira |
| Everhour | Yes | Yes | Yes | Asana, Jira, Basecamp |
Best PM integration: Toggl Track (100+), Everhour (deep native integration with Asana/Jira/Basecamp)
SSO / OIDC (Authentik)
| Tool | OIDC | SAML | LDAP | SCIM |
|---|---|---|---|---|
| Kimai | Yes | Yes | Yes | No |
| Invoice Ninja | No | No | No | No |
| Traggo | No | No | No | No |
| Wakapi | Yes | No | No | No |
| ActivityWatch | No | No | No | No |
| Harvest | No | No | No | No |
| Toggl Track | No | Yes | No | No |
| Clockify | No | Yes | No | No |
| Hubstaff | No | No | No | No |
| TimeCamp | No | No | No | No |
| FreshBooks | No | No | No | No |
| Paymo | No | No | No | No |
| Replicon | Yes | Yes | Yes | Yes |
| BigTime | No | Yes | No | No |
| QuickBooks Time | No | No | No | No |
| Everhour | No | No | No | No |
Best Authentik integration: Kimai (native OIDC, SAML, LDAP), Replicon (OIDC, SAML, LDAP, SCIM), Wakapi (native OIDC)
API Capabilities
| Tool | REST API | Webhooks | Bulk Ops | SDK |
|---|---|---|---|---|
| Kimai | Yes | Yes | Yes | No |
| Invoice Ninja | Yes | Yes | Yes | PHP |
| Traggo | GraphQL | No | No | No |
| Wakapi | Yes | No | No | No |
| ActivityWatch | Yes | No | No | Python |
| Harvest | Yes | Yes | Yes | Ruby |
| Toggl Track | Yes | Yes | Yes | No |
| Clockify | Yes | Yes | Yes | No |
| Hubstaff | Yes | Yes | Yes | No |
| TimeCamp | Yes | No | Yes | No |
| FreshBooks | Yes | Yes | Yes | No |
| Paymo | Yes | Yes | Yes | No |
| Replicon | Yes | Yes | Yes | .NET |
| BigTime | Yes | Yes | Yes | No |
| QuickBooks Time | Yes | Yes | Yes | No |
| Everhour | Yes | Yes | Yes | No |
Best API: Kimai and Invoice Ninja (OSS, full REST with webhooks), Harvest and Replicon (commercial, mature REST with SDKs)
Monitoring Integration
| Tool | Prometheus | Health EP | Logs | SNMP |
|---|---|---|---|---|
| Kimai | No | Docker HC | Stdout | No |
| Invoice Ninja | No | Docker HC | Stdout | No |
| Traggo | No | Docker HC | Stdout | No |
| Wakapi | Yes | /health | Stdout | No |
| ActivityWatch | No | No | Files | No |
| Harvest | No | No | N/A | No |
| Toggl Track | No | No | N/A | No |
| Clockify | No | No | N/A | No |
| Hubstaff | No | No | N/A | No |
| TimeCamp | No | No | N/A | No |
| FreshBooks | No | No | N/A | No |
| Paymo | No | No | N/A | No |
| Replicon | No | Dashboard | N/A | No |
| BigTime | No | No | N/A | No |
| QuickBooks Time | No | No | N/A | No |
| Everhour | No | No | N/A | No |
Best monitoring integration: Wakapi (Prometheus + health endpoint + stdout logs), Kimai and Invoice Ninja (Docker health checks + stdout logs)
Pricing
Self-Hosted / OSS
| Tool | License | Pricing |
|---|---|---|
| Kimai | AGPL-3.0 | Free (plugins paid) |
| Invoice Ninja | AAL/AGPL | Free / Pro $10/month |
| Traggo | GPL-3.0 | Free |
| Wakapi | MIT | Free |
| ActivityWatch | MPL-2.0 | Free |
Commercial SaaS
| Tool | Pricing |
|---|---|
| Harvest | Free (1 user) / $11/user/month |
| Toggl Track | Free (5 users) / $9/user/month |
| Clockify | Free / $4-12/user/month |
| Hubstaff | From $5/user/month |
| TimeCamp | Free (1 user) / $3-9/user/month |
| FreshBooks | From $19/month (5 clients) |
| Paymo | Free (1 user) / $6-18/user/month |
| Replicon | Quote-based (enterprise) |
| BigTime | From $20/user/month |
| QuickBooks Time | From $20/month + $8/user |
| Everhour | Free (5 users) / $9/user/month |
Tools
16 tools.
ActivityWatch
ActivityWatch is an automated, privacy-focused time tracking application that runs locally on the desktop and records which applications and websites the user interacts with.
License: MPL-2.0 (OSS) · Kind: web · Deploy: docker, native, package · SSO: none
BigTime
BigTime is a professional services automation (PSA) and time tracking platform designed specifically for accounting firms, architecture/engineering firms, consulting firms, and IT services companies.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: SAML
Clockify
Clockify is a freemium time tracking platform known for offering unlimited users on its free tier – a unique positioning in the market.
License: Proprietary (proprietary) · Kind: web · Deploy: native, saas · SSO: SAML
Everhour
Everhour is a SaaS time tracking platform that embeds directly into project management tools like Asana, Jira, and ClickUp, offering timers, timesheets, billing rates, and project budgets.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: none
FreshBooks
FreshBooks is a cloud accounting and invoicing platform with integrated time tracking, designed primarily for freelancers, self-employed professionals, and small businesses.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: none
Harvest
Harvest is one of the most established and widely adopted time tracking and invoicing platforms for professional services teams.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: none
Hubstaff
Hubstaff is a SaaS time tracking and workforce management platform with activity monitoring, screenshots, app and URL tracking, GPS and geofencing, timesheets, invoicing, and payroll automation.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: none
Invoice Ninja
Invoice Ninja is the most comprehensive open-source invoicing platform with integrated time tracking.
License: LicenseRef-Elastic-2.0 (source-available) · Kind: web · Deploy: native, docker, saas · SSO: none
Kimai
Kimai is a feature-rich open-source time-tracking application built on Symfony, supporting timers, timesheets, billable rates, project budgets, approval workflows, and invoicing via plugins.
License: AGPL-3.0-only (OSS) · Kind: web · Deploy: native, docker · SSO: SAML
Paymo
Paymo is a project management platform with integrated time tracking and invoicing, designed for agencies, consultancies, and small professional services teams.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: none
QuickBooks Time (TSheets)
QuickBooks Time (formerly TSheets, acquired by Intuit in 2018) is a time tracking platform integrated into the Intuit QuickBooks ecosystem.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: none
Replicon
Replicon is an enterprise-grade time tracking and professional services automation platform serving large organizations, professional services firms, and government agencies.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: OIDC, SAML
TimeCamp
TimeCamp is a time tracking platform that emphasizes automatic time tracking through desktop app and keyword detection.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: none
Toggl Track
Toggl Track is one of the most popular time tracking tools globally, known for its simple one-click timer interface and extensive integration ecosystem.
License: Proprietary (proprietary) · Kind: web · Deploy: saas · SSO: SAML
Traggo
Traggo is a minimalist, tag-based time tracking server written in Go. Unlike traditional time trackers that organize time by projects and clients, Traggo uses a flexible tagging system where every time entry is categorized by user-defined k…
License: GPL-3.0-only (OSS) · Kind: web · Deploy: native, docker · SSO: none
Wakapi
Wakapi is a self-hosted, WakaTime-compatible coding time tracking server. It automatically tracks time spent in code editors and IDEs via WakaTime client plugins, categorizing time by project, language, editor, operating system, and branch….
License: MIT (OSS) · Kind: web · Deploy: native, docker · SSO: OIDC
