Developer & Digital Tools · 🇰🇷 Korea
Korean YouTube Best Upload Time
Korean YouTube audience peak-time heatmap by category with competitor analysis.
About this tool
YouTube Total Duration Calculator takes a list of video IDs / URLs / playlist URLs and queries YouTube Data API v3 to return total watch time, average length, speed-equivalent times (1x / 1.25x / 1.5x / 1.75x / 2x), and a length-distribution chart. Designed to answer "how long is this course at 1.5×?" — handles up to 50 videos / 200-item playlists comfortably. Unlisted / deleted / geo-blocked videos are flagged separately. Export a 1200×630 PNG card. IDs are used for the API call and discarded; no PII is stored, only anonymous aggregate counts.
Use cases
Scenario 1
Course playlist — speed equivalents
For a 30-lecture playlist, see total time alongside 1.5× / 2× equivalents to plan study sessions.
Scenario 2
Bulk 50 videos
Paste 50 video IDs (one per line) for a single batch API call totaling watch time.
Scenario 3
Playlist URL — auto-paginated
Drop a 200-item playlist URL and the tool auto-paginates through all items.
Scenario 4
Private / deleted flags
Inside a playlist, private / deleted videos surface as "N failed lookups" so you know what's missing.
Scenario 5
Length distribution
Use the distribution chart to read the share of sub-5-minute videos and the channel's pacing.
Features
- Auto-detect video IDs / URLs / playlist URLs
- YouTube Data API v3 — batch up to 50
- Total / average / 1x–2x speed equivalents
- Length-distribution chart
- Private / deleted / blocked surfaced separately
- 1200×630 PNG card, unlimited use
Frequently asked
- Q. How many at once?
- A. Up to 50 videos / 200-item playlists is the sweet spot. Beyond 50 needs multiple API calls and slows down.
- Q. What about private / deleted / blocked?
- A. Missing in the API response → flagged as "N failed lookups" and excluded from totals. Geo-blocked items return metadata but not playability.
- Q. How is 1.5× computed?
- A. Simple division — total ÷ speed. In practice pauses / rewinds add 1.2–1.5×, per learning-research data.
- Q. Are IDs stored?
- A. Used for the API call and discarded. Only anonymous aggregate counts are kept under a week — no PII.
- Q. Is this an official YouTube tool?
- A. No. YouTube® is a Google LLC trademark; this is an unaffiliated calculator built on the public Data API v3.
Sources / references
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How we run it / disclaimer
This tool is advisory and does not constitute legal, tax, medical, or financial advice. All calculations and document generation run in your browser; inputs are never sent to a server. Ads follow Google AdSense policy and are kept separate from tool accuracy.