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Platform Portability
Uses Substack subdomain (thefiddler.substack.com). Migrating would require subscribers to re-subscribe at a new address.
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The place for mathematical puzzles and the puzzling community. Two new puzzles every Friday morning!
Data updated Today
David Didau: The Learning Spy
7K subs
0%/wk
The New Books Network Newsletter
8K subs
The Thousand Good Books Project
6K subs
490 paid
Weekly Growth
N/A
Paid Subscriber Retention
Insufficient data
16 of 30 days needed
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$17–$39
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Tracking started recently for Fiddler on the Proof (16 days ago). A growth trend will appear once we have more data points.
Avg Comments
7.7
Avg Likes
6.3
Engagement Rate
0.20%· ~14 likes + comments/post
(comments + likes) / subscribers
Quality Score
Engagement vs Education
0.20% engagement rate
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Quality sub-scores, category percentile, and engagement benchmarks
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| Can Every Day Be First?In 2026, every day of the week is the first day of at least one month. Does this happen every year?Feb 27, 2026 | Subscriber-only |
| Can You Hop in a Spiral?A frog hops around a pond packed with lily pads, spiraling slightly outward with each jump. What’s the tightest spiral it can make?Jan 30, 2026 | Subscriber-only |
| Bingo!On average, how long will it take you to get three (or five) in a row?Jan 23, 2026 | Subscriber-only |
| Can You Brighten Up the Room?A hemispherical lamp is suspended from the ceiling. How large is its shadow?Jan 16, 2026 | Subscriber-only |
| Some Coffee With Your Tea?You pour some coffee into your tea, and then pour some of that back into your coffee. Is there more coffee in your tea or more tea in your coffee?Jan 9, 2026 | Subscriber-only |
Publishing Frequency
Weekly
Last published Apr 3, 2026
0.9 posts/week avg
Education Pricing
$14.16/mo avg
Below average(-44%)
Monetization Readiness
Already monetizing
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