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1. Enter the lecture duration.

Enter a number to calculate minutes: 60 means 60 minutes, 1:30 means 1 minute 30 seconds, and 1:00:00 means 1 hour. You can paste multiple durations, one per line. Load a sample to try it.

2. Select speed and schedule

Online Lecture Playback Speed CalculatorCompare pure viewing time. Course Completion PlannerYou can assign a daily quota by setting the start date, end date, possible days, and time. If the completion status or the original location so far is entered, only the remaining quota is assigned after recalculation.

3. Click the calculate button to save.

Correctly calculated inputs can be restored in the same browser. Changes during input are not saved until you click the calculate button. Incorrect inputs and damaged backups overwrite existing correct data. You can use a JSON backup if saving is blocked.

Each tool keeps its own data. Choose “Create a completion plan from these lectures” in the playback-speed calculator and confirm the import to copy the lecture list and playback speed. Later edits in either tool are not synced.

4. Backup to a JSON file and restore.

Download the current valid input using the ‘JSON Backup’ button of the tool. On another device or browser, you can retrieve the file using ‘Backup Restore’. The file size is up to 1MB. Restoration replaces the data in the tool.

The storage required for free addresses and official domains differs. Back up the files before the address changes, then restore them from the new address. Since the backup includes the course name and plan you entered, verify the content when sharing.

5. Remove unnecessary data

‘Initialize this tool’ in each tool deletes only the data of that tool. The bottom button deletes both tools and settings of this service. Data from other services in the same domain is not deleted.

Did the save fail, or is the result incorrect?

Storage may fail due to private mode, site save blocking, or insufficient storage space. First, save a JSON backup and check browser settings. When damaged data can’t be read, it won’t be silently overwritten; it can be restored via backup or explicit initialization. If data was modified in another tab, backup the current input and refresh.