Pomodoro Timer

Pomodoro Session

{{ phase }} · Round {{ roundIndex }} · {{ playing ? 'Running' : (paused ? 'Paused' : 'Idle') }} · Ends ~ {{ current_finish_time_local }}

Focus {{ focus_min }} min Short {{ short_min }} min Long {{ long_min }} min Long every {{ long_every }} Goal {{ completed_pomos }}/{{ goal_pomos }} Live Goal ETA ~ {{ goal_eta_local }}

Focus length: min

Short break: min

Long break: min

Long break every: focus

Goal (rounds): rounds

Countdown before start: s

Auto‑start next phase:

Tick sound each second:

Beep volume (%):

Beep frequency (Hz):

Beep duration (ms):

Vibrate on phase change:

Prevent screen sleep:

Desktop notification:

Metric	Value	Copy
Phase	{{ phase }}
Round	{{ roundIndex }}
Completed focus	{{ completed_pomos }}
Elapsed (phase)	{{ elapsedDisplay }}
Remaining (phase)	{{ remainingDisplay }}
Ends (local)	{{ current_finish_time_local \|\| '—' }}
Next phase	{{ nextPhaseLabel }}
Goal progress	{{ completed_pomos }} / {{ goal_pomos }}
Goal ETA	{{ goal_eta_local }}

#	Phase	Start	Duration (min)	Copy
{{ r.idx }}	{{ r.phase }}	{{ r.startLocal }}	{{ r.durationMin }}
No upcoming phases.

Shortcuts: Space = Start/Pause · N = Next · S = Stop · F = Fullscreen

Tags: Date Time , Productivity

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Outline clock showing a short hand and a long hand.

Pomodoro sessions are structured cycles of focused work and short breaks that support attention and recovery. They help you plan a sequence you can actually keep so your energy does not fade early.

Results show the current phase, the time remaining, the next phase, and a rolling estimate of when you will finish. You can choose durations that match your task and your day so progress feels steady rather than rushed.

A typical pattern uses twenty five minutes for focus, three to five minutes for a short break, and a longer pause after several rounds. You can set a target number of rounds and see an expected finish time that updates as you move.

For best results start with consistent lengths, keep notifications gentle, and adjust only between phases so your plan stays comparable across days. If your device sleeps the timer may pause, so enable the wake lock when you need it.

Technical Details:

The timer tracks phase time in seconds and derives readable minutes and seconds for display. It reports a simple session progress percentage for the current phase and builds a forward schedule that alternates focus and break periods based on your settings. The estimate to a goal counts remaining focus rounds and inserts the correct breaks between them.

The phase progress percentage is the fraction of elapsed seconds over the phase length, limited between zero and one and shown as a percentage with two decimals. Focus length, short break, and long break are provided in minutes and converted to seconds for timing. A long break occurs after every N completed focus rounds.

p = clamp (\frac{s_{elapsed}}{s_{total}}, 0, 1) \times 100 %

\begin{array}{lll} s_{focus} & = & focus_\min \times 60 \\ s_{short} & = & short_\min \times 60 \\ s_{long} & = & long_\min \times 60 \\ T_{cycle} & = & N \times s_{focus} + (N - 1) \times s_{short} + s_{long} \end{array}

Symbols and units
Symbol	Meaning	Unit/Datatype	Source
selapsed	Elapsed time in the current phase	s	Derived
stotal	Total seconds in the current phase	s	Input → Derived
p	Phase progress percentage	%	Derived
focus_min	Focus length	min	Input
short_min	Short break length	min	Input
long_min	Long break length	min	Input
N	Long break every N focus rounds	count	Input
Tcycle	Total time for one long cycle	s	Derived

Worked example:

\begin{array}{lll} focus_\min & = & 25 \\ short_\min & = & 5 \\ long_\min & = & 15 \\ N & = & 4 \\ T_{cycle} & = & (4 \times 25 + 3 \times 5 + 15) \times 60 = 7800 s = 130 \min \\ p & = & clamp (\frac{750}{1500}, 0, 1) \times 100 % = 50 % \end{array}

A full long cycle totals one hundred thirty minutes; halfway through a focus phase the progress reads fifty percent.

Convert minutes to seconds for phase durations.
Start phase and record a high resolution timestamp.
On each animation frame, compute elapsed seconds.
If elapsed reaches duration, complete the phase.
Choose the next phase: long break every Nth focus, else short break.
For goal time, sum remaining of current phase then alternate breaks and focus until the target count is met.

Validation and bounds extracted from the UI
Field	Type	Min	Max	Step/Pattern	Notes
Focus length	number	1	—	step 1	minutes
Short break	number	1	—	step 1	minutes
Long break	number	1	—	step 1	minutes
Long break every	number	2	—	step 1	focus rounds
Goal (rounds)	number	0	—	step 1	0 disables goal
Countdown before start	number	0	—	step 1	seconds
Auto start next	boolean	—	—	—	plays through boundaries
Tick sound	boolean	—	—	—	one tick each second
Beep volume	number	0	100	step 1	percent
Beep frequency	number	100	—	step 1	Hz
Beep duration	number	40	—	step 10	milliseconds
Vibrate on change	boolean	—	—	—	device support varies
Prevent screen sleep	boolean	—	—	—	requests a screen wake lock
Desktop notification	boolean	—	—	—	permission required

I/O formats
Input	Accepted Families	Output	Encoding/Precision	Rounding
Durations, toggles, goal	Numbers and booleans	Metrics	Strings and numbers	MM:SS display uses floor seconds
—	—	Schedule	Start time in local format	Durations rounded to two decimals (minutes)
—	—	CSV	Comma separated	As above
—	—	JSON	Structured keys for inputs, state, schedule	Exact values

Units, precision, and rounding: times are computed in seconds with integer arithmetic, phase progress shows two decimals, minutes in schedules show two decimals, and the decimal separator follows your locale for rendered times. Percentages use base ten arithmetic.

Networking and storage: processing occurs on your device. Optional features may use a notification permission, a screen wake lock, vibration, audio beeps, clipboard access, and local file downloads. No data is transmitted or stored server side.

Performance: time updates run once per animation frame; schedule generation scales linearly with the number of rows requested.

Security considerations: untrusted text is not accepted as code, and all outputs are plain text files. Clipboard and notification actions follow platform security prompts. Audio is generated locally.

Assumptions & limitations

Long breaks occur every Nth completed focus round; N is at least two.
Background tabs may throttle timers; visual updates can appear less frequent.
Wake lock availability varies by device and operating system.
Vibration is ignored on unsupported hardware.
Notification delivery depends on permission settings and platform policies.
Audio may be blocked until a user gesture enables sound.
Local times use your system locale and time zone.
Heads‑up Pausing at zero may restart the same phase if resumed immediately.
Changing durations mid session affects future phases, not elapsed time.
Copy and download actions can be blocked by restrictive browser settings.

Common edge cases

Non numeric input is treated as zero before clamping.
Negative values are clamped to zero.
Setting goal to zero disables goal calculations.
Setting volume to zero silences ticks and boundary beeps.
Very short beeps under forty milliseconds are lengthened to the minimum.
Beep frequency below one hundred hertz is raised to the minimum.
Hidden or minimized windows may slow the animation loop.
System clock changes affect displayed end times but not elapsed seconds.
Clipboard writes can fail without user interaction.
Notification permission set to denied silences future notifications.

Step‑by‑Step Guide

Pomodoro timing measures focused work and recovery breaks to plan a realistic session.

Set Focus length, Short break, and Long break.
Choose Long break every N focus rounds.
Optionally set a Goal and a short countdown.
Press Start; use Pause, Stop, or Next between phases as needed.
Open Metrics, Schedule, Mix, or JSON to review and share results.
Note Enable notifications or wake lock only when helpful.

Example: focus 25, short 5, long 15, long every 4, goal 4 rounds. The schedule totals about two hours with breaks.

Use a short three second countdown to settle in before a round begins.

FAQ

Is my data stored?

No. Timing, notifications, and exports run on your device. Nothing is sent to a server.

Clipboard and notifications require standard user permissions.

How accurate is the timer?

It uses second resolution with high resolution time for calculations. Background tabs and battery saver modes can slow visual updates on some devices.

What units are supported?

Durations are entered in minutes, countdown in seconds, and times display in your local format.

Can I use it offline?

Yes after the page loads. All timing and exports work without a connection.

Does it cost anything?

No sign up or account is required. Use is unrestricted; any site level licensing applies separately.

How do I schedule a long break?

Set “Long break every” to the number of focus rounds between long breaks. A value of four is a common starting point.

What does Goal ETA mean?

It is the estimated local time when your target number of focus rounds would conclude, including the breaks that fall between them.

Why do notifications or beeps not appear?

Check permission prompts, raise the volume above zero, and confirm sound or notifications are not muted by system settings.

Are keyboard shortcuts available?

Yes. Space to start or pause, N for Next, S for Stop, and F to toggle fullscreen.

Troubleshooting

Start is disabled: ensure focus length is at least one minute.
No sound: set volume above zero and allow audio on this site.
No notification: grant permission and keep the tab open.
No vibration: your device may not support it.
Copy fails: allow clipboard writes or use Download instead.
Clock drifts in background: enable wake lock or keep the screen active.

If the device sleeps aggressively, timing may pause entirely. Turn off battery saver or keep the display awake during sessions.

Advanced Tips

Tip Match round length to task complexity; shorter rounds help with heavy context switching.
Tip Use auto start for momentum on batchable tasks, pause for creative work.
Tip Keep beeps brief and moderate to avoid alarm fatigue.
Tip Set a goal that fits a fixed window such as a morning block.
Tip Review the schedule tab to plan a meeting around your next break.
Tip Adjust the long break every three or four rounds to suit workload intensity.

Glossary

Focus round: A stretch of uninterrupted work.
Short break: A brief recovery between focus rounds.
Long break: An extended recovery after several rounds.
Phase: The current state: countdown, focus, or break.
Cycle: A sequence ending with a long break.
Goal ETA: Estimated local time when the target ends.