A free fragrance collection tracker and wear log, for serious collectors of 4 bottles or 4,000.
Custos keeps a fragrance collection properly: what you own, what you wore, what deserves a rest, and what to wear today — decided from your own shelf, not somebody else's.
What should I wear today?
Custos reads the day on its own — live weather, season, and occasion — and picks from your bottles, with the reasoning shown. No forms to fill out, no filters to set. Open it and the answer is waiting.
Ask Claude, when you want a second opinion
Today's pick is worked out by Custos itself; no AI is involved. For anything it can't anticipate, describe the situation in your own words — a client dinner at a steakhouse, a long-haul flight — and Claude answers with your collection in view. Ask Claude is optional and runs on your own Anthropic API key, which stays on your device. Anthropic bills that usage to your account, and Custos never receives or stores the conversation.
Rotation, done properly
Most apps push you to log more and buy more. Custos tells you when a bottle has rested long enough to wear again — and when it hasn't. You tune the rest logic; your rotation stays even and deliberate. Every wear you log updates the picture — what's rested, what's overdue, what fits tonight. Custos doesn't guess your rotation; it keeps it.
A wear log worth keeping
Every wear is saved with its date and, when Custos has them, the day's weather and the occasion. Add a note to any wear — how it performed, where you wore it, what you'd change — and mark whether it drew a compliment.
Fragrance layering with reasons
Custos suggests layering pairs from bottles you own and explains each one: a simple fragrance completing a complex one, or two scents with enough shared ground to blend — and not so much that nothing new happens. A suggestion with an argument, not a shuffle.
Know your real gaps
No grades, no report cards. Custos names your collection's gaps — borderline, weak, or true — and explains each, so the next bottle is different from the last one on purpose.
A catalog that's right, not just big
2,900 fragrances — and counting. Each one human-reviewed, alias-resolved, and classified by structure, instead of 70,000 scraped rows. Missing a bottle? Add it and wear it tonight; review gates the shared catalog, never you.
Bulk-import from a spreadsheet with the fill-in template — already have your collection listed somewhere? Hand that list to an AI assistant and let it fill the template for you in minutes. Or add a bottle at a time. Full bottles, decants, and testers each get their own entry, and all of them are in the running for today's pick.
Your collection is yours
It lives in your account, visible only to you. Export all of it as CSV or JSON whenever you want — no lock-in. No ads, no affiliate links, no subscription. When you use Ask Claude, Anthropic's Commercial Terms of Service say that Anthropic may not train models on the content sent to its API through the feature.
Free. No subscription. No ads. No streaks, roasts, or judgments.
Create a free account above — runs in your phone's browser, nothing to install.
Questions
Is Custos really free?
Yes. No subscription, no ads, no affiliate links, no locked features. The Terms of Use say so in plain English, and the operating costs are small and operator-funded. The one exception is optional: Ask Claude runs on your own Anthropic API key, and Anthropic bills that usage to you.
How does Custos decide what fragrance to wear today?
It assesses each bottle you own for the day's live weather, season, and occasion — and how recently you've worn it — then ranks them and shows why each one made the list. Tap "Why this?" on any pick for the full reasoning.
Can I import my perfume collection?
Yes — download the fill-in Excel template and import your whole collection in one pass.
What if a fragrance isn't in the catalog?
Add it yourself and use it in your collection immediately. A human reviews it before it joins the shared catalog — but the review never makes you wait.
What is fragrance layering?
Wearing two scents together so they read as one richer composition. Custos suggests pairs from your own bottles and explains what each combination adds.
What is Custos?
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A new version of Custos is available.
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Contributor titles
You earn these titles by adding bottles to the shared catalog. Only bottles an admin approves count. To add one, search for it in + Add bottle; if it isn’t there, tap “Not finding it? Submit it to the catalog.” Adding a bottle you don’t own? Choose “+ Submit to wishlist instead.”
Delete my account
This permanently deletes your account and all of your private data — your collection, wear log, profile, and sign-in. This cannot be undone.
To confirm, type your account email below.
Use Claude with your own API key
If you enable Ask Claude, Custos stores your Anthropic API key only in this browser on this device. Each time you submit a question, your browser sends your question and the following information directly to Anthropic under your own Anthropic API account to generate a response: your “About me” profile text (or “a fragrance enthusiast” if it is blank); your current local date and time, which can reveal your time zone; the day of the week, whether it is a weekday or weekend, and any special-day flag; the season and any shoulder-season blend; a separate time-of-day category (night, morning, day, or evening) derived from the clock hour; weather information derived from your coarse home location (temperature, high temperature, category, and description, but not your coordinates); your active monthly hold and debut overrides and their notes; and, for each bottle in the Core, Extended, Candidate, Archival, Deplete, or Sidelined tier, its name, house, tier, stock, seasons, tags, and your bottle note. Wishlist and Gone bottles are not included. Your profile, override, and bottle notes may contain personal information, so review them before using Ask Claude. Custos’s servers do not receive or store these requests or responses. You can inspect the current instructions sent with a request using Inspect on the Ask Claude card. Anthropic handles information it receives under its applicable terms and privacy policy.
Read Anthropic’s Privacy Policy and Commercial Terms of Service. You can turn Ask Claude off and erase your key and local chat history at any time in Settings → Ask Claude.
Report this catalog entry
You are reporting the shared catalog record for
This is about the shared record everyone sees — not your own collection, tiers, or notes, which stay private either way.
An administrator reviews every report and can correct or remove the entry. For rights complaints you can also email legal@custos-fragrance.com.
