What does that stamp actually mean?

Paste in a date code or describe a maker mark. Get likely dates, factory info, and authenticity flags in seconds. Built for thrift flippers, antique dealers, and vintage collectors.

Decode a Label

Or describe the mark:

Enter a code above and press Decode to see results.

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How to read tiny marks

Get the right light

Hold the item at an angle under a bright lamp. Many marks are pressed into the surface and only show up with side lighting. A cheap 10x loupe makes a huge difference for stamps smaller than a pencil tip.

Check the bottom and inside

Glassware marks are almost always on the base. Ceramics marks go on the bottom or inside the foot ring. Electronics date codes are usually on a paper sticker or stamped into the metal chassis.

Watch for red flags

If a "Made in Japan" stamp sits next to a date code that says 1943, something is off. Japan did not export to the US during WWII. Mismatched fonts, modern-looking ink, or marks that rub off easily are also warning signs.

Numbers are not always years

A four-digit number on the bottom of a bowl is usually a mold or shape number, not the year it was made. Cross-reference the shape with known catalogs before listing it as "1961" just because 1961 is stamped on it.

My decoded collection

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Real-world scenarios

The estate sale bowl

You find a green glass bowl with "8" pressed into the base and no other marks. The seller says it is "Depression glass, 1930s." The decoder shows that a single digit is usually a mold number, not a year. You check the pattern against known Depression glass guides and confirm it is a Hocking Glass "Block Optic" pattern from 1929 to 1933. The digit 8 is mold-specific. You list it with the pattern name and date range, not just "1930s." Buyers searching for Block Optic find your listing.

The suspicious figurine

A porcelain figurine has a blue crown stamp and "Made in Japan" in purple ink. The seller claims it is a 19th-century Meissen. The decoder flags that Meissen used a crossed-swords mark, not a crown, and that "Made in Japan" stamps were not required until after 1891. The combination of a crown mark and Japanese origin stamp points to a mid-20th-century export piece, not an antique. You pass on the purchase.

The transistor radio

A small radio has "3C7712" stamped inside the back cover. The decoder reads this as year-ending-in-3, month C (March), factory code 7712. That places it in March 1973 or 1983. The radio has a Sony logo and a Japanese band selector, which fits the 1970s Sony ICF series. You list it as "Sony transistor radio, circa 1973" and include the date code in the description for serious collectors.

Common questions

What if my code does not match anything?
Try entering just the numbers without letters, or reverse the order. Some makers stamped the year first, others last. If it still does not match, use the mark description checkboxes instead of the code field.
Can this prove an item is fake?
No. This tool flags common red flags like mismatched date ranges for a known maker's active years. Authentication requires hands-on inspection. Use this as a first pass, not a final verdict.
Does it work for items from outside the US?
Yes. The decoder includes common European and Asian maker marks, especially for glassware and ceramics. Coverage is strongest for items made between 1920 and 1990.
Is my data saved anywhere?
Nothing leaves your browser. Saved lookups live in localStorage on your device only. Clear your browser data and they are gone.
Why does the same code show multiple possible dates?
Some manufacturers reused code formats across decades. A code like "73" could mean 1973, 1983, or 1993 depending on the maker. The decoder shows all plausible matches so you can narrow it down using other clues like color, style, and weight.