r/whatsthatbook
What's that book called?
Founded February 2013 · Public — anyone can post
Can't remember the title of the book you've enjoyed reading? Crowdsource it to readers on Reddit!
Members
341,367
341K
Online now
—
not captured in the last snapshot
Posts per day
—
no sample yet
Comments per post
—
no sample yet
Growth · 7d
—
not enough history yet
Growth · 30d
+0.7%
+2.3K members · ≈37d
Promo tolerance
—
not assessed yet
Last post
—
no sample yet
Distinct posters
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no sample yet
Tracking since Aug 18 · growth spans are the real distance between snapshots, not rounded windows. Posts/day is measured from the community’s own newest posts on Reddit, not from what Prowlo happens to crawl.
Member growth
Similar by content
Communities that discuss what r/whatsthatbook discusses.
Looking for a specific novel? Request it here and connect with readers who can help you find amazing stories.
Just providing recommedations on books readers would love!!
This is a moderated subreddit. It is our intent and purpose to foster and encourage in-depth discussion about all things related to books, authors, genres, or publishing in a safe, supportive environment. If you're looking for help with a personal book recommendation, consult our Weekly Recommendation Thread, Suggested Reading page, or ask in r/suggestmeabook.
A place to share and discuss book reviews. Write your own reviews, share professional and amateur book reviews from elsewhere, and discuss the reviews posted.
See the full lists on similar subreddits.
r/whatsthatbook — frequently asked
How many members does r/whatsthatbook have?
r/whatsthatbook has 341,367 members as of our most recent crawl on Sep 24. Prowlo re-checks tracked communities on a rolling schedule, so this figure moves rather than sitting frozen at whatever it was when a scraper last ran.
Is r/whatsthatbook growing?
Over the last ≈37 days r/whatsthatbook changed by +0.7% — a gain of 2.3K members. We compare against the nearest snapshot we actually hold and state the real span rather than rounding it to a clean "30 days".
How active is r/whatsthatbook?
We don't have a reliable posting-rate sample for r/whatsthatbook yet. Subscriber count alone is a poor guide to whether a community is active, so treat this one as unverified until the next sample lands.
When was r/whatsthatbook created?
r/whatsthatbook was founded in February 2013 and is a public — anyone can post community. Age matters: an older community with steady growth has survived Reddit's moderation churn; a young one with a spike may not.
Can I promote my product in r/whatsthatbook?
We don't have a promo-tolerance read for r/whatsthatbook yet. Default to the safe approach: read the sidebar rules, contribute in threads where you gain nothing, and mention your product only when it is the honest answer to someone's question.
How do I monitor r/whatsthatbook for mentions?
Hit Watch on this page. Prowlo starts crawling r/whatsthatbook into your Dataset — every new post indexed and embedded, searchable semantically, queryable by your AI agent over MCP, and able to trigger keyword alerts in Slack. Prowlo is read-only; it never posts on your behalf.
Can my AI agent read r/whatsthatbook's stats?
Yes. Everything on this page is one MCP tool call away: catalog_get_subreddit returns r/whatsthatbook's members, growth, promo tolerance and similar communities as typed JSON — free, no credits. Connect your agent to api.prowlo.com/mcp and it can vet the community and start watching it in the same conversation.
Read-only · Human-in-the-loop
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