Discover / checkdigit.openverbs.com

EAN / UPC / GTIN check

■ Challenge detected

Validate a GTIN barcode number — EAN-8, UPC-A (12), EAN-13 or GTIN-14 — by the standard mod-10 check digit. Length selects the scheme.

Listed price
$0.002
Challenge detected
9 of the last 9 checks
Median response
185 ms
Last checked
16 Oct, 18:49 UTC
In our index since
26 Sept 2026

Endpoint

curl -i https://checkdigit.openverbs.com/v1/ean
# 402 Payment Required: pay with an x402 client (USDC on Base),
# then send the same request again with the payment attached.
5 listed endpoints · on x402 Bazaar

Checks and payment terms on this page refer to the endpoint above. Other listed endpoints have not been checked individually.

Base URLhttps://checkdigit.openverbs.com/v1

  • POST/isbn$0.002Validate an ISBN-10 (mod-11, trailing X allowed) or ISBN-13 (GTIN mod-10) book number. Length after removing spaces/hyphens selects the scheme.
  • POST/luhn$0.002Validate a number by the Luhn (mod-10) algorithm — the scheme behind credit/debit card numbers and many IDs. Spaces and hyphens are ignored. A mismatched check digit is a successful { valid: false }.
  • POST/imei$0.002Validate a 15-digit mobile device IMEI by its Luhn check digit. Spaces and hyphens are ignored.
  • POST/routing$0.002Validate a 9-digit US ABA bank routing number by its weighted (3,7,1) mod-10 checksum. Spaces and hyphens are ignored.
  • POST/ean$0.002Validate a GTIN barcode number — EAN-8, UPC-A (12), EAN-13 or GTIN-14 — by the standard mod-10 check digit. Length selects the scheme.

A dash means the listing gives no price or method. Copy buttons copy the full URL.

Showing 5 of 5 listed endpoints.

Agents can find it through the Superstables MCP server and JSON API: GET /api/v1/services/checkdigit.openverbs.com

Recent checks

2 Oct 2026One bar per check, showing up to 20 recent checks. Coloured bars show relative response time, with a minimum visible height; full-height grey bars mean no challenge was detected. “Challenge detected” means HTTP 402 or another detected payment-challenge signal.16 Oct 2026
All 9 checks
When (UTC)ResultHTTPResponse
16 Oct, 18:49 UTCChallenge detected402216ms
15 Oct, 11:37 UTCChallenge detected402187ms
14 Oct, 00:19 UTCChallenge detected402167ms
12 Oct, 00:34 UTCChallenge detected402168ms
10 Oct, 10:04 UTCChallenge detected402228ms
9 Oct, 03:33 UTCChallenge detected402163ms
8 Oct, 00:44 UTCChallenge detected402185ms
6 Oct, 21:30 UTCChallenge detected402521ms
2 Oct, 17:03 UTCChallenge detected402185ms

Questions

Did our last probe detect a payment challenge?

At our last probe on 16 Oct, 18:49 UTC, it returned HTTP 402 or another detected payment-challenge signal. This check did not test payment, delivery or compatibility with the Superstables client.

What price is recorded for EAN / UPC / GTIN check?

Its listed price is $0.002.

What payment terms does EAN / UPC / GTIN check advertise?

The listing advertises x402, Base and USDC. It names cdp as its facilitator. Check the seller's current payment challenge and authentication requirements before paying.

Where is EAN / UPC / GTIN check listed?

In x402 Bazaar. Superstables first indexed it on 26 Sept 2026.

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