0 interval completions
Run independent named countdowns and repeating interval sequences from absolute deadlines with local session recovery.
Loading local session…
Countdown · Cycle 1
Space start / pause · R restart selected timer
Select a timer to edit its controls. Running timers keep counting when you switch.
Enable sound, then press Test sound or start a timer to activate browser audio. Visual completion alerts remain available if audio is blocked.
Editing: Timer 1
One Name:seconds per line, for example Work:60 then Rest:15. Up to 20 intervals. Applying a sequence resets this timer.
Choose a .json timer backup, up to 2 MiB. Your current session is replaced only after validation and confirmation.
No backup selected yet
Absolute deadlines prevent interval drift. Browser suspension, a closed tab or blocked audio can delay/prevent alerts. Reopened sessions catch up and show completion counts; repeated missed alerts are consolidated.
Space starts/pauses the selected timer; R restarts it outside inputs. Presets and Apply duration configure a single countdown, replacing the selected timer’s interval sequence. Reset returns to the configured sequence without starting; Restart & start begins it immediately.
Sessions are saved in this browser. Export backups before clearing browser data or resetting the session. Save errors and stored-data recovery controls remain visible above the timer.
Browser-only local storage; no account or cloud backup. Clearing browser data or a storage failure can remove recoverability. Export backups. Unsaved drafts remain in memory and save errors stay visible.
Enter your values locally; no inputs are uploaded.
Check validation feedback before reviewing the browser-generated result.
Review the explanation, copy supported outputs or reset the workspace.
Configure the local session, use the relevant controls and shortcuts, review results/saved state and explicitly export portable backups.
Up to 10 timers with hours/minutes/seconds, quick presets, start/pause/resume/restart and adding/subtracting current-interval time. Up to 20 named sequence steps can repeat. Absolute deadlines catch up missed intervals without accumulated tick drift. Optional Web Audio sound, volume and persistent visual completion counts are included. Audio requires browser permission/user activation; closed tabs and browser suspension can delay or prevent alerts. Space and R control the selected timer; JSON backup/restore and presentation mode are local.
Inputs and sessions stay in browser memory and local IndexedDB. No user-file uploads, accounts, paid services or cloud storage are used. Clearing browser data can delete sessions; storage failures remain visible and backups are recommended. Ordinary page requests may still be logged.
Remaining time is computed from absolute deadlines. On a late tick/reopen, interval boundaries advance from the prior deadline and missed repeating cycles are counted without replaying every alert.
Yes. Up to 10 named timers run independently. Configure up to 20 Name:seconds steps, repeat a sequence, pause/resume, restart or add/subtract time from the current interval.
No. Sound is optional and requires browser audio activation; volume and test sound are provided. Browser suspension, blocked audio or closed tabs can delay/prevent sound. Visual completion counts remain available after recovery.
Hours/minutes/seconds and 5-second/1/5/25-minute presets configure durations. Space starts/pauses the selected timer and R restarts it outside inputs. JSON session backup/restore and presentation mode are included.
Session data is stored only in this browser’s dedicated IndexedDB record. No account, paid API, external processing or user-file upload is used. Clearing browser data/private-session cleanup can remove it; keep exported backups.
Save completion is reported only after an IndexedDB transaction completes. Quota failures keep drafts in memory and the previous stored snapshot intact. Corrupted data is not automatically overwritten; recovery JSON and explicit replacement controls are provided. Revision checks prevent silent cross-tab overwrites. Sessions/backups are bounded to 2 MiB; undo snapshots are session-only and bounded.
Run independent named countdowns and repeating interval sequences from absolute deadlines with local session recovery.
Up to 10 timers with hours/minutes/seconds, quick presets, start/pause/resume/restart and adding/subtracting current-interval time. Up to 20 named sequence steps can repeat. Absolute deadlines catch up missed intervals without accumulated tick drift. Optional Web Audio sound, volume and persistent visual completion counts are included. Audio requires browser permission/user activation; closed tabs and browser suspension can delay or prevent alerts. Space and R control the selected timer; JSON backup/restore and presentation mode are local.
Remaining time is computed from absolute deadlines. On a late tick/reopen, interval boundaries advance from the prior deadline and missed repeating cycles are counted without replaying every alert.
Yes. Up to 10 named timers run independently. Configure up to 20 Name:seconds steps, repeat a sequence, pause/resume, restart or add/subtract time from the current interval.
No. Sound is optional and requires browser audio activation; volume and test sound are provided. Browser suspension, blocked audio or closed tabs can delay/prevent sound. Visual completion counts remain available after recovery.
Hours/minutes/seconds and 5-second/1/5/25-minute presets configure durations. Space starts/pauses the selected timer and R restarts it outside inputs. JSON session backup/restore and presentation mode are included.
Session data is stored only in this browser’s dedicated IndexedDB record. No account, paid API, external processing or user-file upload is used. Clearing browser data/private-session cleanup can remove it; keep exported backups.
Save completion is reported only after an IndexedDB transaction completes. Quota failures keep drafts in memory and the previous stored snapshot intact. Corrupted data is not automatically overwritten; recovery JSON and explicit replacement controls are provided. Revision checks prevent silent cross-tab overwrites. Sessions/backups are bounded to 2 MiB; undo snapshots are session-only and bounded.