About HammerAlert

One auction calendar across the houses collectors already follow.

Written and maintained by Laurens Lokker, HammerAlert founder.

What HammerAlert is

HammerAlert is a cross-house auction calendar for collectors, advisers, and market watchers who want upcoming sales in one place instead of spread across dozens of house websites. The public auction pages cover more than 150 auction houses and marketplaces, from global houses such as Christie's, Sotheby's, Bonhams, Phillips, and Drouot to regional specialists. Each sale is normalised into the same browse structure so it can be found by house, region, category, date, and detail URL.

The account product turns that public index into a personal calendar. You choose the houses, regions, and collecting categories that matter, then subscribe once from Apple Calendar, Google Calendar, Outlook, or another calendar app. When HammerAlert sees new auctions or changed dates, the calendar feed updates in place. A weekly email digest is available for people who prefer inbox summaries, but the core product is the live calendar view.

Why it exists

Auction houses are good at publishing their own sales, but following each house separately creates noise. Every newsletter, saved search, and alert setting uses a different cadence. Important sales can be buried between marketing emails, reminder messages, and duplicate announcements for the same auction. HammerAlert was built to reduce that overload: one neutral layer that watches the calendars and lets the collector decide which signals are worth keeping.

The aim is not to replace house catalogues. Final lot research, condition reports, registration, and bidding still happen with the auction house. HammerAlert is the discovery and planning layer before that: what is coming up, where it is, which category it belongs to, and whether it deserves a place in your own auction calendar.

How it works

HammerAlert uses source-specific scrapers and parsers to read public auction calendars, then normalises the result into a shared index. The pipeline deduplicates repeat appearances of the same sale, classifies each auction into a category, preserves source links, and keeps route-level canonical URLs stable for search engines and users. The browse pages expose the same index by all auctions, category, region, and auction house.

The approach is practical rather than magical: structured source data when it is available, conservative fallbacks when it is not, and manual review when a house changes its calendar. For product questions, see the FAQ and support articles. For data handling, see the privacy policy. A more detailed methodology page documents the collection, normalisation, and quality checks in one place.