Gemsmakers · Antique Market Research Desk

Antique Auction Estimate & Hammer Results Journal

Keep your own record of what auction houses estimated and what lots actually brought. Compare hammer prices with estimate ranges, see how often results landed inside them, and review your evidence across multiple sales.

✦ User-entered sale records⌖ No external price feed⇩ Export CSV or JSON

A practical historical estimate tracker

This journal is for collectors, dealers, researchers, and auction watchers who want a consistent record of estimate ranges and hammer outcomes. Log the published low and high estimate, the hammer price, the sale date, and a short note about the object or sale.

Use the summary to spot how your selected sample behaves. A hit rate describes only the records you entered; it does not establish the accuracy of an auction house or predict the next result.

Add an auction result

Enter figures in the same currency. Record the hammer price before buyer’s premium, tax, shipping, or other costs.

Your estimate-range summary

Only complete records in one currency are included together; mixed currencies are summarized separately to avoid misleading comparisons.

Sale / object	Date · lot	Estimate range	Hammer	Versus range	Vs. midpoint	Action

Your journal is empty. Add a recorded sale above to begin comparing estimates and hammer prices.

How the comparison works

Inside estimate rangeThe hammer price is at or above the low estimate and at or below the high estimate.

Estimate-range hit rateInside-range results divided by records with valid low, high, and hammer values, shown as a percentage.

Midpoint variance(Hammer price − estimate midpoint) ÷ estimate midpoint. Positive means above the midpoint; negative means below it.

Mean / median varianceAverage and middle midpoint variance across complete records in the same currency. Median is less affected by a few exceptional results.

Build a useful sale sample

Keep like with like. Track object type, period, condition, and sale format in your notes before comparing groups.
Copy estimates as published. Note whether a source labels them as a pre-sale range and keep any later revisions in the note.
Separate hammer from total cost. This journal compares hammer price to estimate. Fees and taxes belong in a separate total-cost calculation.
Record unsold lots carefully. A passed or bought-in lot has no public hammer result. Do not enter zero as if it sold for zero.
Retain your source. Save the sale catalogue, lot page, date accessed, and any currency or condition context with your research file.

Read the summary with care

A small or self-selected set of lots can be skewed by one unusually strong result, a category mix, condition differences, reserve policies, or changing buyer demand. The mean and median here describe the records saved in this browser only.

The tool performs no live lookup, currency conversion, appraisal, authenticity review, or market forecast. For a financial decision, verify the sale record and consult an appropriately qualified specialist.

Antique auction estimate questions

Does a hammer price include the buyer’s premium?

No. A hammer price is the winning bid before buyer’s premium and other charges. Auction terminology and reporting can vary, so check the sale record before entering the figure.

What if the estimate low and high are the same?

The tool accepts a single-value estimate range and uses that value as the midpoint. A hammer exactly at that value is considered inside the range.

How is a mixed-currency journal handled?

Each currency is summarized separately. The tool does not convert currencies or combine unlike amounts into one total.

Where are my auction notes saved?

Records stay in this browser’s local storage and are not sent to Gemsmakers. Export a backup before clearing site data or using another device. Do not store private information on a shared device.

Using historical antique auction results responsibly

An estimate is an auction house’s pre-sale guide, while the hammer price records a bidding outcome under particular sale conditions. Their comparison can help organize historical research, but a journal cannot isolate why a lot sold where it did. Attribution, condition, provenance, competing bidders, reserve terms, catalogue reach, and timing can all matter. Capture those context clues in the note field and consult the original sale listing whenever possible.

Long-tail research searches such as “antique auction hammer price versus estimate tracker,” “historic furniture auction estimate results,” or “how often antique lots sell within estimate” are best answered with well-documented, comparable sales. This free tool helps structure those records; it does not provide a market-wide dataset or claim predictive power.

The interface stores data locally in your browser. CSV and JSON exports are generated on your device. No sale records or object notes are submitted to an external service.