The Scento Decoder turns the cryptic string of letters and digits stamped on the bottom of a perfume bottle into a manufacturing date you can act on. The point of this page is to show our work. Every confidence tier we publish, every house we cover, every limitation we hit — all of it is below.
We built the decoder to make its confidence and limitations explicit. Some manufacturers have date formats that can be decoded with documented rules; others publish no public algorithm. The result therefore distinguishes decoded dates from estimates instead of presenting every output as equally certain.
A batch code is a manufacturer-issued identifier that ties a specific bottle of perfume to a specific production run. Most fragrance houses print theirs in tiny sans-serif on the underside of the glass and on the outer carton. The exact format varies wildly — some manufacturers encode the date directly, others use it as a reference number that maps back to internal production logs.
Three things you can do with the decoded date:
- Estimate freshness. A well-stored eau de parfum holds well for roughly five years from production. Past that, top notes flatten, citrus turns, and the dry-down loses its lift. A decoded date tells you how much shelf life is realistically left.
- Spot inconsistencies on second-hand bottles. When the seller claims "bought last month, tested twice" but the code decodes to 2017, you know something is off — either the seller is mistaken or the bottle is older stock.
- Cross-check against other signals. A code that decodes to a plausible date can still be copied onto a counterfeit. Inspect its typography and location together with the seller, packaging, bottle construction, any per-bottle serial or QR code, and the scent itself.
The decoder cannot tell you whether a bottle is genuine — that requires physical inspection — but a date that fits, combined with correct typography and sticker placement, is a useful first filter.
There is no industry-wide batch-code standard. The current public registry routes supported brands to implemented parser modules, including:
- Estée Lauder-style 3-character parser for supported Tom Ford and Jo Malone codes.
- Dior 4-character parser for supported Dior codes.
- L'Oréal Luxe 6-character parser for supported Armani and Yves Saint Laurent codes.
- Coty 4-digit parser for supported Versace codes.
- Creed year-letter parser and Chanel cycle parser for the supported formats described by those modules.
Not every bottle from a supported house will match one public format, and a matching format does not authenticate a bottle. Other houses publish no public decoding rule; those brands use the separate Tier C estimate path and remain labelled ESTIMATED.
When you submit a brand and a code, the decoder does this:
- Look up the brand in our internal registry.
- Read the brand's ordered list of decoder schemes. Most brands point to a single scheme (Tom Ford → Estée Lauder 3-character). Some brands carry two or three schemes, applied in order, because of regime changes — for example, Calvin Klein went from Unilever's scheme (pre-2005) to Coty's 4-digit scheme (post-2005), and the decoder tries Coty's scheme first because the vast majority of CK bottles in circulation post-date the transfer.
- Apply each scheme to the input. If the scheme matches the format and produces a plausible date (not before the brand's launch year, not in the future), return that date with a confidence label.
- If no public scheme produces a plausible date, the founder-approved Tier C exception returns a deterministic plausible date labelled ESTIMATED. It is not a decoded manufacturer date and must not be treated as one.
The first three steps parse the submitted string against the registered scheme. The Tier C exception is a separate deterministic estimate path and remains visibly labelled.
Every result the decoder returns is labelled with one of four tiers. We are deliberately public about what each tier means.
- HIGH — the registry classifies the brand under a documented scheme and the submitted code matches that parser. This is still a date decode, not proof that the bottle is authentic.
- MEDIUM — a supported Tier B parser matched, but the underlying format is only partially documented or has known exceptions. Treat the decoded date with more caution than a HIGH result.
- LOW — the submitted code did not produce a successful decode, for example because the brand is unknown, the input is empty, or the format is unrecognised. LOW does not supply a verified manufacturing date.
- ESTIMATED — the brand does not publish a public decoder algorithm. The Tier C exception returns a deterministic plausible date, not the bottle's verified production date. Treat it as directional only and contact the brand with the code if the exact date matters.
The ESTIMATED tier is the one we get the most pushback on, so to be fully transparent: when an algorithm doesn't exist, an estimate is necessarily a model-driven guess. We make the model as good as we can — bounded by the brand's launch year, bounded above by the current date, biased toward recent production for high-volume SKUs — but it remains a guess. Treat it accordingly.
- Pre-2002 Chanel. Chanel's modern cycle starts in 2002. Anything older returns a range that includes pre-cycle years where data is sparse.
- Vintage Hermès letter pairs. Some pre-1980 letter pairs map to multiple plausible decades. We mark these LOW.
- Niche houses with no public algorithm. Initio, Nishane, By Kilian, Byredo, Le Labo, Frédéric Malle, Mancera, Montale, Maison Crivelli, Ex Nihilo. We have not yet published per-brand pages for these. They will be added in V1.5 once we have enough intake data to support a documented format-pattern estimate.
- Decants and split bottles. A decant inherits the batch code of the parent bottle, but second-hand decants are often missing the carton with the printed code, and the laser-etched code on the bottom of a 100 ml bottle is not visible once split. The decoder works with whatever code you can find, but if the only code is on a third-party atomizer, it tells you nothing about manufacturing date.
- Bottle-only versus carton. Some manufacturers print different codes on bottle and carton. For Tier A houses these usually agree; for some Tier C houses they don't. Always prefer the bottle code when both are available.
Scento states that its decants are poured from original full-sized bottles sourced through authorised European retailers. Manufacturer batch codes apply to those original bottles. A Scento decant vial does not carry the original bottle's code, so do not treat a code printed on a third-party atomiser as source-bottle provenance.
The decoder can help interpret a code from an original bottle, but it cannot authenticate a loose decant by itself.
You have three reasonable options:
- Check the seller and sourcing. For a full bottle, prefer the brand or an authorised retailer. For a decant, look for a clear sourcing statement and transparent seller details.
- Contact the brand's customer service. Some houses may be able to confirm a production date if you provide the code.
- Cross-check on a fragrance forum. Basenotes, Fragrantica, and Reddit r/fragrance have active threads where users post codes for community decoding. The collective knowledge there is good but inconsistent — treat as another data point, not an authoritative answer.
The decoder draws on three categories of source:
- Public manufacturer guidance where it exists.
- Implemented format rules in the decoder registry, with confidence labels that distinguish documented and partial schemes.
- Community examples used as supporting observations rather than authoritative manufacturer records.
If you find a bottle the decoder cannot read, contact the brand directly for the most authoritative answer.
