Storyline
Captain Kane and Professor Briggs come across a mysterious place with dangerously oversized creatures.
Captain Kane and Professor Briggs come across a mysterious place with dangerously oversized creatures.
See estimated worth (fair value), annual growth, last sale, time-based trends, and liquidity by grade.
No tracked sales yet.
No tracked sales yet.
No tracked sales yet.
Not enough history to estimate by grade yet.
Average days to sell vary by grade (—), ranging from the fastest grade to the slowest grade
Search by title and issue to explore market data, sales history, and real-time pricing trends for each grade.
Gain insight into key metrics such as Fair Value, Compound Annual Growth Rate (CAGR), and time-based average sale prices by issue and grade.
Quickly find comics like Tales To Astonish #1 priced below fair value across the web through auction sites like eBay, based on recent market data.
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Underval is a free comic-book analytics and listings platform. We estimate fair value by grade, display annual growth rate, show recent sales and sales history, and surface active listings.
We aggregate public online sales from major marketplaces and auctions such as eBay and Heritage Auctions, then normalize and de-duplicate them by issue and grade.
Fair value blends recent realized sales with longer-term trends, outlier filtering, and grade-level liquidity. It’s an informational estimate, not an offer.
Values update as new sales appear. Each grade’s “Updated on” date reflects the most recent sale we’ve matched for that grade.
We track Universal CGC-graded copies across common scale points (e.g., 0.5–10). Availability varies by issue and observed market activity.
No. Underval provides data and estimates for research purposes only. Always do your own diligence before buying or selling.