Cardmarket Buyer & Seller Tools
A free Firefox and Chrome extension for Cardmarket. Bulk-list a ManaBox export, spot listings over or under market, reprice your stock, export wants.
Tools for buying and selling Magic cards on Cardmarket.
Bulk Listing fills Cardmarket's listing form from a ManaBox CSV. Price Check flags listings priced over or under market — on your own stock when selling, or on any seller's page to spot deals when buying. Reprice to Market then rewrites your own prices in one pass, and a wants list exports to Moxfield. Everything runs in your browser; only current trend prices are fetched from manavalue.org.
One install covers every tool, and the extension is the whole install — no manager, no switch to find. On Safari and Opera, and on any browser you would rather keep the tools updating the moment they ship, install the userscript instead ↓
What you get
| Tool | What it does | Where it runs |
|---|---|---|
| Bulk Listing | Fills the listing form from a ManaBox CSV export. | Stock → Listing Methods → Bulk Listing |
| Price Check | Tints listings priced over or under market trend. | Your Stock → Offers, or any seller's Offers |
| Reprice to Market | Rewrites your prices to market, after a preview. | Your Stock → Offers |
| Moxfield export | Copies the wants as a Moxfield decklist. | Any wants list |
Install it
- 1
Add the extension
Firefox 140 and Chrome 111 or newer. The Chrome one installs on Edge too, from the same page.
- 2
Check that it runs
Signed in to Cardmarket, open your Stock → Offers page. A 📊 Stock Price Check panel appears in the bottom-right corner and starts loading trend prices. That panel is the install working — every other tool arrives the same way, on its own page.
Nothing there? Work down the list below.
Safari, Opera, or anywhere you want updates first: the userscript
The same tools, run by a userscript manager. Because the extensions carry the script whole — both stores forbid fetched code — a new version reaches them only once the store review clears, while the userscript picks it up on the next page load.
- Tampermonkey
Chrome, Edge, Firefox, Safari, Opera
Chrome/Edge: open the extension's details page and turn on Allow user scripts.
- Violentmonkey
Chrome, Edge, Firefox
Chrome/Edge: open the extension's details page and turn on Allow user scripts.
- Userscripts
Safari
Enable it in Safari → Settings → Extensions, then allow it on cardmarket.com.
With one in place, install the userscript — your manager opens a confirmation page listing what it may run on. What you install is a small loader (2.6.0), which fetches the current tools script (5.17.1) on each page load, so your manager keeps showing the loader's version. Prefer to pin one? Install the main script directly and update it by hand.
No panel? Start here
No panel at all, on any page
With the extension, check it is enabled and not switched off for private windows (about:addons on Firefox, chrome://extensions on Chrome). With a userscript manager it is almost always the manager, not the script: on Chrome or Edge, userscripts stay switched off until you turn on Allow user scripts on the manager's own details page, and in Safari the Userscripts extension has to be enabled and then allowed on cardmarket.com.A panel on some pages but not others
The tools only attach to the pages they are for: Bulk Listing, an Offers page (your own stock or any seller's), and a single wants list — the wants overview that lists your lists has no panel of its own; open a list first. The address must also be www.cardmarket.com; a link without the www. runs nothing.Still nothing — check the console
Open the browser console on a Cardmarket page (F12 → Console) and look for one line:[MV-CM loader v2.6.0] running cardmarket-tools v5.17.1The extensions print it too, with their own version. No line at all means the script never ran — go back to the first case. A red error instead means the fetch from manavalue.org was blocked: an ad blocker, a DNS filter or a corporate proxy. Allow manavalue.org and reload.My manager says version 2.6.0, the site says 5.17.1
Both are right, and this is the userscript route only. Your manager tracks the small loader (2.6.0), which rarely changes; the tools it pulls in on each page load are versioned separately (5.17.1) and update themselves. The console line above tells you which tools version actually ran. The extensions carry the tools whole instead — both stores forbid fetched code — so each shows one version, and may sit a release behind until its review clears.
Bulk Listing
List a whole ManaBox collection without typing every row. The script reads your CSV and fills quantity, price, condition, language, and foil on Cardmarket's Bulk Listing table. Open Bulk Listing
How to use it
- 1
Export a CSV from ManaBox
Open the collection or binder, tap Export → CSV, and keep the default columns.
- 2
Open Bulk Listing and pick an expansion
On Cardmarket, go to Stock → Listing Methods → Bulk Listing and choose a set. A 📋 ManaBox → Cardmarket panel appears bottom-right and loads price data automatically.
- 3
Upload your CSV and click Fill Form
Pick your export in the panel, then hit ▶ Fill Form. Matched rows are filled and highlighted green. The panel shows how many entries are still unplaced — change page or expansion and run Fill Form again; the queue carries over.
No CSV? Fill Form just writes a trend price into every row — handy if you entered quantities by hand.
- 4
Review and put on sale
Spot-check the highlighted rows, then use Cardmarket's Put Card(s) On Sale button.
Price Check
See which listings drift from market at a glance — rows tint when priced over or under trend, foil and exact printing included. Works on singles and sealed alike (boosters, displays, sets). On your own stock it surfaces what to reprice; on another seller's Offers page it highlights cards going for under market. Open your Stock
How to use it
- 1
Open Stock → Offers
A 📊 Stock Price Check panel appears bottom-right and loads trend prices automatically.
- 2
Read the tinted rows
Each listing shows its trend price and the gap next to your price:
- Over market — priced above trend.
- Under market — priced below trend: money left on the table on your own stock, a deal on someone else's.
Listings within your threshold aren't flagged. Printings with no trend price show no data and aren't tinted.
- 3
Load everything, then sort or filter
Click ⏬ Load all pages to pull your whole paginated stock into one table (requests are throttled; stop and resume any time). Then sort by Name, Offer, or vs Market, and tick Hide fairly-priced rows to keep only the mispriced ones — over- and under-market. (On another seller's page the same tick narrows to just the under-market deals.)
On your own stock, Hide empty expansions strips the hundreds of (0) entries from Cardmarket's expansion filter, leaving only the expansions you actually have offers in.
- 4
Adjust prices on Cardmarket
Edit listings as usual — the panel re-checks live, so corrected rows lose their tint. To rewrite every price at once instead, see Reprice to Market.
Reprice to Market
Price Check tells you what drifted; this rewrites it. One click computes a market-based price for every listing in your stock table — same rounding and undercut as the Bulk Listing tool — and shows you every change before a single price is written. Your own stock only. Open your Stock
How to use it
- 1
Load the stock you want to reprice
On Stock → Offers, click ⚖ Update prices to market in the bottom-right. Only the rows currently in the table are included, so run ⏬ Load all pages first to cover your whole stock — the preview warns you when pages are still missing.
- 2
Set how you want to price
Round to and Undercut % are the same settings the bulk lister uses — change them here and both tools follow. Min difference (€) skips listings that would move by less than that, so a few cents of drift doesn't fill the list.
- 3
Review the before → after preview
Every change is listed with current → new price and the delta per copy, sortable by card, quantity, price or delta, each with a tick you can clear. The footer totals what your stock is worth now versus after, and estimates how long the run takes. Untouched listings are counted with the reason — already at target, below your minimum, no market data, or not editable.
- 4
Apply, and watch it go
Confirm and each listing is updated through Cardmarket's own edit form, throttled to stay within rate limits. Rows tick off as they land, failures are marked with the reason on hover, and you can stop mid-run — anything not yet attempted is left untouched. Repriced rows are re-checked, so their tint updates in place.
Wants list → Moxfield
Turn a Cardmarket wants list into a decklist you can paste straight into Moxfield, instead of retyping it card by card. Open your wants lists
How to use it
- 1
Open a wants list
A 🃏 Export to Moxfield panel appears bottom-right with the decklist already built — one line per card, quantities merged.
- 2
Pick the whole list or just a selection
Tick Only ticked rows to export just the wants you have selected in the table.
Wants pinned to a single expansion export with that set code; wants that accept any printing stay bare so Moxfield picks. Sealed product is left out — Moxfield only knows cards.
- 3
Copy and import
📋 Copy puts the list on your clipboard, or Copy & open ↗ copies it and opens Moxfield's import page in a new tab — paste it there and import. (Moxfield has no public import API, so the paste is yours to make.)
Review before you submit
These tools automate data entry and analysis. Trend prices come from public Cardmarket data and can be stale or missing. You're responsible for the listings you publish and the prices you set — check the highlighted rows and start with a small batch. No warranty.
Two tools write to your account: Bulk Listing fills the form (you still press Put Card(s) On Sale), and Reprice to Market updates live prices once you confirm its preview. Everything else only reads the page. Nothing is ever bought or sold on your behalf.
Frequently asked questions
Is the userscript free?+
Yes. One install covers every tool — Bulk Listing, Price Check, Reprice to Market, and the Moxfield wants export — free to use. No account, no subscription.
Does my collection or stock data get uploaded anywhere?+
No. Bulk Listing parses your ManaBox CSV locally in the browser, and every other tool reads the Cardmarket page you are already on. They only fetch public JSON price files from manavalue.org. The contents of your collection, stock, cart, and wants lists are never sent to any server.
Which browsers and userscript managers are supported?+
There is an extension for Firefox 140 and newer (addons.mozilla.org) and for Chrome 111 and newer (Chrome Web Store, which also installs on Edge). Either one is the whole install: no userscript manager, and no switch to turn on. On Safari, Opera and anywhere else, use a userscript manager instead — Tampermonkey, Violentmonkey, or the Userscripts extension for Safari. On Chrome and Edge a manager also needs 'Allow user scripts' turned on on its details page; until you do, it runs no userscript at all and no panel appears. In Safari, enable the extension and allow it on cardmarket.com.
Is there a browser extension instead of a userscript?+
Yes, in both stores: "Cardmarket Tools (manavalue.org)" on addons.mozilla.org for Firefox 140+, and on the Chrome Web Store for Chrome 111+ (which installs on Edge too). Each is the same script with the same four tools and the same permissions — it runs only on Cardmarket's Offers, Bulk Listing and Wants pages and collects nothing. The difference is how it updates: the userscript pulls the current tools on each page load, while an extension carries them whole, because both stores forbid remotely hosted code, so a new version reaches you once the store review clears. On Safari and Opera, use a userscript manager.
What does the Price Check script flag?+
On any Cardmarket Offers page — your own stock or another seller's — it tints each listing by whether it is priced over or under market trend, taking foil and the exact printing into account. Sellers use it to find listings to reprice; buyers use it to spot cards going for under market. A listing is only flagged when it is past both an adjustable percentage threshold and a minimum euro difference.
Can it check my whole stock at once instead of page by page?+
Yes. A 'Load all pages' button in the bottom-right fetches every page of your paginated stock — wherever you start — and merges the rows into the current table, so the whole stock is price-checked in one pass. Once everything is loaded the pager is removed and the table can be sorted by name, offer price, or distance from market. Requests are deliberately spaced out to respect Cardmarket's rate limits, and loading can be stopped and resumed at any point.
Where do prices come from?+
Cardmarket trend price for the matched product, or trend-foil for foil rows, with a fallback to the lowest market price when no trend is available. For Bulk Listing you can apply a minimum price, round-to step, and undercut percentage on top.
Can it reprice my existing listings instead of just flagging them?+
Yes. On your own Stock → Offers, 'Update prices to market' computes a market-based price for every listing in the table using the same rounding and undercut settings as the bulk lister, then shows a before/after preview: each change with its delta, sortable and individually tickable, plus what your stock is worth before and after. Nothing is written until you confirm, updates are throttled to respect Cardmarket's rate limits, and the run can be stopped at any point. Run 'Load all pages' first to cover your whole stock rather than the page on screen.
Can I export a Cardmarket wants list to Moxfield?+
Yes. Open any wants list and the panel builds a Moxfield-format decklist — one line per card, quantities merged, sealed product left out. Copy it, or use 'Copy & open' to copy it and open Moxfield's import page in a new tab. Wants pinned to a single expansion carry that set code; wants that accept any printing are exported bare so Moxfield picks. Moxfield has no public import API, so the paste is yours to make.
Are etched foils handled?+
Yes. ManaBox 'etched' rows are listed as foil and priced from Cardmarket's foil trend. Cardmarket does not track etched foils separately.