Buy on CDX Auction

Timed marketplace for coins and bullion from independent shops and software-powered dealers. Accounts are free — register, bid or offer, win, then pay the selling shop (CDX does not hold the money). No buyer premium. See also Why CDX and the word list.

1. Register & verify

Create your account

Open Register with a real email.
Use a strong password (8+ characters, letter + number).
Confirm the link in your email (from CDX Auction) within 24 hours. Bidding and make offer are locked until verified.

2. Browse

Find lots

Live lots on the browse page — search, sort, filters
Great deals — strong value scores — filter
Below metal value — ask under raw metal — filter
Ending soon — /ending.php
Lots with video — /prime.php
Modern mint & sealed — /fresh-outs.php
Live metal board — gold, silver, platinum, palladium on the home page

Cards & stores

Metal value and % vs metal on bullion; great / fair / premium labels
Guide-price chips from saved values when the shop linked them — details
☆ to watch (login required)
Open seller stores; favorite sellers for new listings

Mobile: menu on the left. Lot pages keep a sticky bid / Buy Now / offer bar while you scroll.

3. Your max bid

How max bids work

Enter the most you will pay as a fixed dollar max, or on bullion use a % of metal value (moves when metal prices move; optional hard $ ceiling). We only raise your bid as needed to keep you ahead (by the lot’s step), up to your maximum. Other bidders do not see your max.

Minimum is the next required bid (starting price, or current + step)
If you’re already high, you can raise your max without changing the public price until someone competes
If another max is higher, you stay outbid until you raise yours
Bid history may mark automatic steps as auto
Bids are binding. Activity in the last ~2 minutes can add time to the clock so others can respond
Lot pages update while open (price flash, history, high/outbid status)

4. Make offer

Private negotiation

Make offer is not a public bid. It only appears when the seller enabled Allow make offer (default on for new listings).

Offer must clear the starting bid (or next public bid) and stay below Buy Now when Buy Now is set
Shop can accept, counter, or decline (typically ~48 hours if unanswered)
If accepted (or you accept a counter), the lot sells at that price → normal win payment due
You can withdraw a pending offer before the seller acts
Offer activity shows in the notification bell (and often by email)

5. Buy Now & live metal

Fixed Buy Now

Optional instant purchase at a set price. A max bid at or above Buy Now can complete an instant purchase at the Buy Now price.

Buy Now that follows metal prices

For gold, silver, platinum, or palladium. Price tracks live metal + the shop’s markup, with an optional minimum; never below the starting bid. Look for the Live metal badge and the pricing panel on the lot.

6. Win & pay

Payments docs →

Pay the selling shop

Check Wins, Payments, and your win email / bell
Use Pay seller — card, PayPal, Zelle, bank transfer, etc. as they enable
Offline “I paid with…” lists only methods that shop turned on
If you owe one shop for several lots, use Pay all to this dealer
Keep shipping details current under Settings

7. Portfolio, sets & notifications

Collector tools →

Portfolio & set checklist

Portfolio — wins + open high bids; metal-value comparison when the item is bullion
Set builder — year map (owned / chasing / live / missing) for major series
Click a gold year for the live lot; missing years search browse

Notifications

Bell — header inbox for outbid, ending soon, wins, offers
Email — outbid, ending soon, won, favorites, optional daily digest
Toggle under Settings — full detail: Notifications guide

Account areas

My bids · Wins · Portfolio / Set builder · Watchlist · Favorites · Feedback · Payments · Settings (shipping + email prefs).