Free userscript for Cardmarket sellers — bulk-list a ManaBox CSV, and flag stock listings priced over or under market.
One free userscript · two tools
One browser userscript that automates the tedious parts of running a Cardmarket stock. Bulk Listing fills the listing form from a ManaBox CSV; Price Check flags which of your existing listings are over or under market. Both tools run locally and pull live trend prices from manavalue.org.
The script runs inside a browser extension that executes userscripts. Pick one if you don't already have it:
Then install the userscript — one install covers both tools below. Your userscript manager will show a confirmation page listing what the script can do — review it and click Install.
Bulk Listing
Cardmarket's Bulk Listing tool shows every card in a chosen expansion as a table — you fill quantity, price, condition, language, and foil into each row by hand, one set at a time. This userscript reads your ManaBox CSV in the browser and fills those rows for you, using live trend prices from manavalue.org.
In ManaBox, open the collection or binder you want to list, tap Export, and pick CSV. Keep all default columns — the script reads Name, Set code, Collector number, Scryfall ID, Quantity, Condition, Language, and Foil.
Sign in to Cardmarket, then go to Stock → Listing Methods → Bulk Listing. Choose an expansion from the dropdown — Cardmarket renders a paginated table of every card in that set, with empty quantity, price, condition, language, and foil fields ready to fill.
When the page finishes loading, a panel labelled 📋 ManaBox → Cardmarket appears in the bottom-right. It immediately fetches price and product data from manavalue.org.
In the floating panel, click Upload ManaBox CSV and pick your export. The file is parsed locally — nothing about your collection is uploaded anywhere.
The script walks Cardmarket's table rows for the current expansion, matches each one against your CSV, and fills quantity, price, condition, language, and foil. Every row it wrote is highlighted in green so you can see exactly what changed before submitting.
Cardmarket paginates large sets, and your CSV likely spans several expansions. The panel shows "N unplaced" for everything still queued. Click → for the next page, or switch the expansion dropdown, then hit Fill Form again — the remaining queue persists across pages and expansions.
No CSV uploaded? Fill Form still works — it just writes a trend price into every row on the page. Handy if you already entered quantities manually and only need prices.
Scan the highlighted rows and spot-check a few prices, especially anything you care about. When you're happy, use Cardmarket's Put Card(s) On Sale button to publish the listings for the current page.
Open the ⚙ Price strategy section in the panel. Settings persist across sessions.
Price source: Cardmarket trend for the matched product (or trend-foil for foils), falling back to the lowest market price when no trend is available. The strategy above is applied on top.
The script resolves each CSV row to a Cardmarket product using — in order — Scryfall ID, then (Set code + Collector number), then Set code alone. If your CSV has three Counterspells from different sets, each lands in the right row.
foil and etched both list as foil. Etched foils are priced from Cardmarket's foil trend (Cardmarket doesn't track etched separately).
ManaBox language codes (en, de, fr, ja, …) and condition labels (near_mint, light_played, …) are mapped to Cardmarket's dropdown values automatically.
Your CSV never leaves your browser. The script only fetches two public JSON files from manavalue.org for prices and product IDs. No account, no upload, no tracking on the listing page itself.
Price Check
Open your Cardmarket stock and this userscript checks every listing against the current trend price — foil and exact printing taken into account — then tints the row red when you're priced over market and green when you're under. A Load all pages button pulls your entire paginated stock into one table, so you can check everything at once instead of clicking through page by page.
Sign in to Cardmarket and open your Stock → Offers page — the list of everything you currently have for sale.
A panel labelled 📊 Stock Price Check appears in the bottom-right and fetches trend prices from manavalue.org automatically.
Each matched listing is checked against market and tinted in place, with the trend price and the percentage gap shown next to your price:
Rows within the threshold are left untinted — they're priced fairly, so there's nothing to do.
Your stock is paginated. Click ⏬ Load all pages in the bottom-right to fetch every page — wherever you start — into the one table, so your whole stock is checked at once. Requests are spaced out automatically to stay clear of Cardmarket's rate limits, and you can stop and resume at any point. Once everything is loaded the pager disappears, and you can click the Name, Offer, or vs Market headers to sort the merged table.
Edit the flagged listings directly in Cardmarket's stock table as usual. The panel re-checks as the page updates, so cleared rows lose their tint once you bring them back in line.
All controls live in the panel and persist across sessions. A listing is only flagged when it breaches both thresholds — this keeps penny cards quiet.
Price source: Cardmarket trend for the matched product, using trend-foil for foil listings. The panel mirrors Cardmarket's light/dark theme.
These tools automate data entry and analysis only. They do not verify that the cards on the page match your CSV, that prices reflect current market conditions, or that Cardmarket has the right product variant selected. Trend prices come from public Cardmarket data and may be stale, missing, or wrong for newer or niche printings.
You are responsible for the listings you publish. Mana Value and the scripts' authors accept no liability for mispriced cards, mismatched products, lost revenue, refunds, account penalties, or any other consequences of using these userscripts. Always review the highlighted rows before clicking Cardmarket's submit button, and start with a small batch.
Trust model: the script you install is a small loader that fetches the main script from manavalue.org on every page load. This means new features ship without you re-installing — but it also means you're trusting this domain to serve safe code while you're logged into Cardmarket. If you're uncomfortable with that, install a pinned copy from the main script URL instead and update it manually.
Provided as-is, with no warranty. By using the userscripts you accept these terms.