Quick Answer: The best open source time tracking for developers in 2026 is ActivityWatch for fully local automatic tracking, Wakapi if you want self-hosted WakaTime-style coding stats, and Watson or Timewarrior if you live in the terminal and prefer a CLI. For team timesheets and invoicing, Kimai is the mature web app, and Super Productivity is the best all-in-one for solo devs who want tasks and a timer together. All of them let you own your data. None of them prove the work was yours, which matters more in 2026 than it used to.
Open source time tracking appeals to developers for a simple reason: you can read the code, host it yourself, and keep your activity data off someone else's server. That is a real advantage when the data is "every keystroke and window title from my workday." The trade is that you maintain it, and most of these tools answer "how long" without answering "who actually did this and what shipped." Below is a tested, ranked rundown, an honest comparison table, and the one limitation every open source tracker shares.
What "open source time tracking" gets you (and what it does not)
If you have ever balked at a proprietary tracker uploading your activity to a SaaS dashboard, the appeal here is obvious. Open source means you can self-host, audit the code, and avoid a subscription. This section covers what that buys you and where it quietly stops.
What you gain is control. Self-hosted tools like ActivityWatch and Wakapi keep raw activity on your machine or your own server, which is the right call for client work under NDA, regulated environments, or anyone who does not want their coding patterns sold back to them as "insights." You also avoid per-seat pricing, and you can extend the tooling because the source is right there.
What you do not get is accuracy for free, and you almost never get proof. Automatic trackers infer activity from window focus and input events, which is a decent benchmark but drifts the moment you are reading docs, in a meeting, or watching an AI agent generate a 400-line diff while you think. This is the part that catches most developers off guard. In 2026, commit volume and "active editor minutes" are both weak proxies for real effort, because an agent can produce a huge commit in seconds and a one-line fix can follow an hour of reasoning. An open source timer tells you a number. It does not tell anyone else that the number, or the code behind it, is yours.
The comparison table
Before the rankings, here is the fast view. "Auto" means it tracks passively without you starting a timer. "Self-host" means you run the server yourself. "Code-aware" means it understands editors, languages, or git rather than generic app usage.
| Tool | Type | Auto | Self-host | Code-aware | Best for |
|---|---|---|---|---|---|
| ActivityWatch | Desktop, local | Yes | Yes (local) | Partial (via plugins) | Privacy-first automatic tracking |
| Wakapi | Self-hosted server | Yes (with editor plugin) | Yes | Yes | Self-hosted WakaTime-style stats |
| Watson | CLI | No (manual start/stop) | N/A (local files) | No | Terminal-native project timing |
| Timewarrior | CLI | No (manual) | N/A (local files) | No | Scriptable, taskwarrior users |
| Kimai | Web app | No (manual + timer) | Yes | No | Team timesheets and invoicing |
| Super Productivity | Desktop app | Partial | Optional sync | No | Solo devs wanting tasks + timer |
1. ActivityWatch: the privacy-first default
Most developers who want open source tracking land on ActivityWatch first, and for good reason. It is the closest thing to a RescueTime replacement that never leaves your machine.
What it is: A free, open source automatic time tracker that records active window, browser tab, and editor activity locally. Cross-platform, with a growing set of community watchers (including editor integrations).
Best for: Developers who want passive, automatic tracking with zero data leaving their device.
Pros: Genuinely local by default, actively maintained, extensible via watchers, no account required. The web dashboard is decent and the data is yours in a queryable database.
Cons: Setup and useful reporting take effort. Out of the box it tracks app and window usage, not code-level detail, so "2 hours in VS Code" does not separate deep work from idle focus. You maintain it.
Pricing: Free, open source.
Verdict: The strongest open source pick for privacy. If your main objection to commercial trackers is the cloud, start here. For a deeper look at where it fits and where it falls short, see our ActivityWatch alternative breakdown.
2. Wakapi: self-hosted WakaTime stats
If what you want is WakaTime-style coding stats without sending your data to WakaTime's servers, Wakapi is the answer most developers do not know exists.
What it is: A lightweight, open source, self-hosted server that is compatible with WakaTime's editor plugins. You point the same plugins at your own Wakapi instance and get per-language, per-project, per-editor stats on infrastructure you control.
Best for: Developers who like the WakaTime data model but want to self-host it.
Pros: Reuses the mature WakaTime plugin ecosystem, small footprint, full data ownership, good dashboards for languages and projects.
Cons: You still install a per-editor plugin in every editor, so it inherits WakaTime's biggest weakness: nothing is tracked in an editor you forgot to set up, and terminal or agentic work outside a supported editor is invisible. You run and update the server.
Pricing: Free, open source (you pay for hosting).
Verdict: The best self-hosted option if you want language and editor breakdowns. If the per-editor plugin requirement is the dealbreaker, read coding time tracker without an IDE plugin and the wider WakaTime alternatives roundup, which compares the hosted tool against self-hosted and git-based options.
3. Watson: terminal-native timing
Some developers do not want a dashboard at all. They want to type a command when they start, type another when they stop, and get clean reports. Watson is built for exactly that.
What it is: An open source command-line time tracker. watson start, watson stop, tag by project and client, then watson report or watson log.
Best for: CLI-first developers and freelancers who bill by project and want timing without a GUI.
Pros: Fast, scriptable, frictionless once it is muscle memory, stores data in plain local files you can back up or pipe into anything.
Cons: Manual. If you forget to start it, the session never happened, which is the failure mode of every manual timer. No automatic capture, no code awareness.
Pricing: Free, open source.
Verdict: Excellent for disciplined terminal users who genuinely will run the commands. If you know you will forget, a passive tool serves you better.
4. Timewarrior: scriptable and Taskwarrior-friendly
Timewarrior is the pick for the developer who already lives in plaintext productivity tooling and wants timing to compose with everything else.
What it is: An open source CLI time tracker from the Taskwarrior project. Start, stop, tag, and slice time intervals with powerful reporting and tight Taskwarrior integration.
Best for: Power users who want scriptable, hackable interval tracking that plugs into an existing CLI workflow.
Pros: Deeply flexible reporting, integrates with Taskwarrior, plain local storage, great for automation.
Cons: Steeper learning curve than Watson, also fully manual, no code or git awareness. The flexibility is the cost.
Pricing: Free, open source.
Verdict: Choose it over Watson if you want more reporting power or already use Taskwarrior. Otherwise Watson is the gentler CLI start.
5. Kimai: open source timesheets for teams
When the requirement is invoicing or a shared team timesheet rather than personal stats, the CLI tools stop being enough. Kimai is the mature open source option here.
What it is: A web-based, self-hosted open source time tracking app aimed at freelancers and teams, with projects, customers, rates, exports, and invoicing features.
Best for: Small agencies, freelance teams, and contractors who need billable timesheets they can self-host.
Pros: Full multi-user support, invoicing and exports, customer and rate management, actively maintained, runs on your own server.
Cons: Manual timer, not code-aware, and it is a general business tool rather than a developer one, so it knows nothing about your repos or commits. Setup is heavier (PHP, database).
Pricing: Free, open source self-hosted (a hosted cloud plan exists separately).
Verdict: The best open source choice for billable team time. If you are a solo developer invoicing clients and want the hours to come from real work instead of a manual timer, pair the timesheet mindset with tracking coding time from git.
6. Super Productivity: tasks and timer in one
The last pick is for developers who want their to-do list and their time tracking in the same window, without a SaaS account.
What it is: An open source desktop app combining task management, a Pomodoro-style timer, and time tracking, with optional sync and integrations (Jira, GitHub, GitLab).
Best for: Solo developers who want a single app for tasks plus time, fully under their control.
Pros: Polished, offline-capable, integrates with issue trackers, no mandatory cloud, pleasant to use day to day.
Cons: Time capture leans on you starting work on a task, so it is semi-manual. Not git-aware or code-level. Sync is your responsibility.
Pricing: Free, open source.
Verdict: The best all-in-one for an individual developer who wants structure around the day, not just a stopwatch.
The honest limitation every open source tracker shares
Every tool above measures, to varying degrees, how long you were active. Not one of them produces evidence that the work and the hours are yours. That gap did not matter much when humans typed every line. It matters now.
This is the claims-versus-proof problem in miniature. A self-hosted timer says "you worked 6 hours." A client, a recruiter, or an investor has only your word for it, the same way a green contribution graph is only a claim that you were active and a resume is only a claim that you shipped. When an AI agent writes a large share of the diff, two questions get harder at once: how long it genuinely took, and how much you drove. An audited record of real work settles both. A number in a dashboard does not, no matter how open the source.
This is an argument for being clear about what a timer can and cannot do for you, not against open source tracking. If your goal is personal awareness or billable hours you trust yourself on, these tools are excellent and you should own your data.
Where DevClocked fits
Full disclosure: I build DevClocked, in public, as @builtbysketch.
If your hard requirement is open source, self-hosted, or air-gapped, DevClocked is not your tool. It is a hosted product, not an open source project, and ActivityWatch or Wakapi will serve you better when "I must run the code myself" is non-negotiable. If you only need personal awareness or a CLI you trust, Watson or Timewarrior are lighter and free. Use them.
DevClocked earns its place when the question stops being "how many hours" and becomes "what did I actually ship, and can I prove it." It leads with leverage and output: it measures what you and your AI coding agents (Claude Code, Cursor, Codex, and others) produced, not just minutes in an editor. The mechanism is a git baseline (a benchmark from commit history, no per-editor plugin needed) combined with telemetry from a lightweight extension and an editor-agnostic CLI that also captures terminal and agentic work, with a model learning the relationship between commits and real activity so the time is calibrated rather than guessed. The output is a profile that proves what you shipped, audited to source. That is the layer open source timers do not reach.
