LibraryThing Web Collection Value Estimator

WHAT IT DOES

This tool helps you estimate the value of your LibraryThing book collection. It scans collection pages for book titles, authors, editions, conditions, and estimated values (from user-added fields or price data). The panel displays total estimated collection value, average value per book, value range, and a breakdown of high/medium/low value books. The most valuable books are listed with their values, and the summary shows value distribution by category. A trend indicator shows changes in total value over time (tracked across sessions). Quick "Search" buttons open LibraryThing searches for high-value books, and an export function copies collection value data as CSV to your clipboard.

WHERE IT RUNS

The script activates on LibraryThing pages (librarything.com), including collection pages, catalog views, and shelf listings. It automatically detects book data using multiple extraction strategies that work across different LibraryThing layouts. The panel appears as a draggable overlay that stays accessible as you browse your collection.

HOW TO USE

Navigate to your LibraryThing collection page. The panel will appear showing your collection's estimated value. The total value is displayed prominently, with a summary showing book count, average value, total, and range. Toggle "Show Low/Hide Low" to control whether low-value books appear in the list. Select your preferred currency (USD, EUR, GBP) for price display. Set the "Refresh (s)" input to control how often the script checks for updates (default 60 seconds). The "Scan" button manually refreshes the data, and "Export CSV" copies your collection value data to your clipboard. The most valuable books are listed with their values, and the trend shows how your collection value has changed over time.

THE TECHNICAL MECHANISM

The script employs a multi-strategy DOM extraction approach for LibraryThing's collection interface. It first attempts structured selectors targeting known class names like .book-item, .catalog-item, and .book-row, then falls back to heuristic detection of book containers based on content patterns including "by", "pages", and book-related keywords. Title extraction uses dedicated title elements or parsing the first non-numeric text line. Author extraction uses author elements or "by [Author]" patterns. Value extraction captures currency amounts from the page with support for $, €, and £ symbols. Condition extraction identifies book condition keywords (fine, very good, good, fair, poor, new, like new, acceptable). Category/shelf extraction captures shelf or tag information. The value tracking system stores collection snapshots using GM_setValue with timestamps, enabling trend analysis. The trend indicator compares the current total value with the previous stored value. The CSV export generates a formatted file with Title, Author, Value, Condition, and Category columns. All settings and history are persisted using GM_setValue.

THE PANEL

The panel is fully draggable by its header and remembers its position on the page across sessions. It can be collapsed to a small bubble using the minimize button, then restored by clicking the bubble. The panel resizes automatically to fit its content and can be closed with the Escape key or by clicking the close button. The panel's position and state persist globally, so it returns to the same location on subsequent visits.

PLEASE NOTE

Requires the free BotGentz extension to run. LibraryThing may update its site structure, which could affect the script's ability to detect collection data — updates will be released as needed. All collection data is read from the page and displayed locally; nothing is transmitted externally. Value estimation depends on the data available on the page—user-entered values or external price data. The script does not automatically fetch external price data; it uses what is displayed on the page. The CSV export copies data to your clipboard for personal use. This tool is for informational purposes only and is not affiliated with LibraryThing. Estimated values may not reflect actual market value.