Paste the inscriptions stamped between the grooves and the label. Find out which plant pressed your record, when it was made, and how it compares to other pressings.
Enter a matrix code above to see what it reveals.
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A quick guide to understanding what those scratches and stamps mean.
The dead wax is the smooth, non-grooved ring between the last track and the label. Hold the record under a bright light at an angle. You will see stamped numbers, etched letters, and sometimes hand-scratched symbols. The text is often tiny and mirrored, so a loupe helps.
Stamped marks are pressed into the vinyl during manufacturing. They usually come from the pressing plant. Etched marks are scratched into the lacquer before pressing, often by the mastering engineer. Both matter, but they tell you different parts of the story.
The catalog number is the label's identifier for that release (like "ILPS 9080" or "AL 34060"). It tells you what album and format, but not which pressing. Two copies with the same catalog number can be from completely different eras.
Pressing plants add their own codes. "STERLING" means Sterling Sound's plant. "MASTERDISC" is the Long Island plant. "PORKY" refers to engineer George Peckham. Knowing the plant helps date the pressing and assess quality.
Symbols like triangles, stars, or the letter "G" (for George) indicate which stamper was used. First stamper pressings are often sought after because the audio quality degrades slightly with each generation of stamper. Collectors track these carefully.
US pressings tend to use all-caps stamped codes. UK pressings often mix stamped and etched text with matrix-side numbers like "A-3U." Japanese pressings frequently include English and Japanese characters, plus "AP" or "P" prefixes. Each region has its own pattern language.
Things that trip up even experienced collectors.
The mastering engineer's initials and the stamper symbol both appear in the runout, but they mean different things. "RL" on early Atlantic pressings refers to Robert Ludwig, the mastering engineer. A triangle or "▽" symbol usually marks the stamper generation. Mixing them up leads to wrong conclusions about pressing order.
Some labels kept the same catalog numbering system for 20 or 30 years. A Columbia record with "XSM168637" could be from 1968 or 1985. You need the plant code and stamper symbol to narrow it down. The decoder flags these cases with a date range instead of a single year.
Bootleg pressings sometimes copy the matrix text from an original pressing. The code will decode correctly, but the vinyl weight, label print quality, and cover art give it away. Always check physical details alongside the matrix data.
If nothing comes up, try searching just the catalog number or just the plant identifier. Some inscriptions include extra text like side numbers ("A-1") or cut numbers ("RE-1") that vary copy to copy. Stripping those away and searching the core pattern often works.
Japanese records often have English matrix text on one side and Japanese characters on the other. The English side usually follows a pattern like "25AP 1234 A1." The Japanese side may include the label name in kanji. Search the English side first for the best results.