ReplyDial

Free tool

YouTube API quota calculator

Every tool that reads or answers YouTube comments through the API spends from the same daily budget: 10,000 units per project. A posted reply costs 50; reading 100 comments costs 1. See what a day of replying really uses.

Reading comments

132 units

6 × 22 per refresh

Posting replies

1,000 units

20 × 50 each

Of the daily 10,000

11.3%

1,132 units a day

With this reading pattern, one project can post at most 197 replies a day before YouTube stops it until midnight Pacific time.

Cost of each operation

OperationAPI methodUnits
Post a replycomments.insert50
Read up to 100 comment threads on a videocommentThreads.list1
List up to 50 uploadsplaylistItems.list1
Look up a channelchannels.list1
Search (avoid it)search.list100

Source: Google’s quota cost table. Reset happens at midnight Pacific time.

Questions

What is the YouTube API quota?
Every Google Cloud project that uses the YouTube Data API gets 10,000 quota units a day by default. Each API call costs a fixed number of units. When the project runs out, every call fails until the quota resets at midnight Pacific time. Google can raise the limit on request after reviewing the app.
How much does a comment reply cost?
Posting a reply (comments.insert) costs 50 units. Reading a page of up to 100 comment threads (commentThreads.list) costs 1 unit. Listing a channel's uploads costs 1 unit per page of 50 videos.
So how many replies a day can one tool post?
At most 200 if it reads nothing at all (10,000 ÷ 50). Realistically 150 to 190 once reading is counted. This is why bulk or "reply to everything" tools break, and why the quota is shared across every user of a hosted tool unless it has been granted an extension.
Does replying by hand in YouTube Studio use quota?
No. Quota applies to third-party apps using the API. YouTube's own website and Studio are not metered this way.
How does ReplyDial handle it?
It reads comments only when you open or refresh your inbox, posts only what you approve, paces replies a few seconds apart, and keeps per-day and per-video caps that protect both the quota and your channel's standing with YouTube's spam systems.

Want the answer for your own channel?

The unanswered comments checker counts what is waiting on your last 20 videos. ReplyDial then helps you answer it without breaking the quota or YouTube’s rules.