COUNTER 5

COUNTER 5 (formally the COUNTER Code of Practice, Release 5, or 'COP5') is the current international standard governing how publishers, aggregators, and other content platforms must record and report usage statistics — searches, investigations, and requests — for the electronic resources (journals, databases, books, and multimedia items) they license to libraries and consortia. A usage report qualifies as 'COUNTER 5 compliant' only if it is produced from one of COP5's defined Master Report templates, uses COP5's controlled Metric_Types vocabulary, applies COP5's double-click and robot-filtering deduplication rules consistently, and (where automated) is retrievable via the COUNTER API (formerly called SUSHI, the Standardized Usage Statistics Harvesting Initiative). The standard exists so that a usage number from one publisher platform means the same thing as the equivalent number from another, letting libraries compare cost-per-use and make collection-development and renewal decisions on a like-for-like basis.

ByCASRAI Editorial Board

· Last updated 23 Jul 2026

Worked examples

Is an instance

A library evaluating whether to renew a journal package pulls a COUNTER 5 Title Master Report (TR) from the publisher's admin portal, filtered to the Total_Item_Requests metric type, to see full-text download counts per title over the subscription year — then divides each title's annual cost by that figure to calculate cost-per-use for the renewal decision.

Is an instance

A consortium's electronic resource management system automatically retrieves monthly COUNTER 5 Platform Master Reports (PR) from a dozen different vendor platforms overnight via the COUNTER API (SUSHI), rather than library staff logging into each vendor's admin interface separately to download reports by hand.

Looks similar, but isn't

Not an instance

A vendor's raw Google Analytics or web-server access-log export of file downloads is not a COUNTER 5 report, even though it also counts usage: it hasn't been through COP5's required double-click deduplication and robot/crawler filtering, doesn't use COP5's controlled Metric_Type vocabulary (e.g. Total_Item_Requests, Unique_Item_Requests), and isn't structured as one of the four Master Report types — so its numbers aren't comparable to another platform's COUNTER 5 figures even if both are counting the same underlying activity.

COUNTER 5 is the fifth, and current, release of the COUNTER Code of Practice — a standard maintained by Project COUNTER (now operating as COUNTER Metrics Limited) that defines how content providers must measure and report usage of the electronic resources they license to libraries. “COUNTER” stands for Counting Online Usage of Networked Electronic Resources. The Code of Practice was first published in 2002; Release 5 (also referred to as “COP5”) was published in 2017, with compliance required of report providers from January 2019, superseding Release 4 (published 2012). A subsequent update, Release 5.1, was published in 2022 and became the required compliance baseline from January 2025, with Release 5.0-only reports no longer accepted after that transition.

Why it exists

Before a common code of practice, publisher usage reports were not comparable: one platform might count every page view, another only full-text downloads, and a third might not filter out repeated clicks or crawler/robot traffic at all. A library trying to decide which subscriptions justify their cost — a core input to collection-development and renewal decisions — had no reliable way to compare a usage number from one vendor against the same metric from another. COUNTER’s Code of Practice standardizes the report structure, the underlying activity definitions, and the deduplication/filtering rules so that a given metric means the same thing everywhere it’s reported.

The four Master Reports

COP5 defines usage data through four Master Reports, each covering a different resource level. Libraries and consortia typically pull pre-filtered “Standard Views” of these reports for routine use, but can also query the underlying data by other dimensions (access type, data type, YOP — year of publication — and more):

Platform Master Report (PR) — usage summarized at the level of an entire vendor platform.
Database Master Report (DR) — usage of individual databases on a platform, including searches and result-clicks.
Title Master Report (TR) — usage of individual journal, book, or other titles, the report most commonly used for per-title cost-per-use analysis.
Item Master Report (IR) — usage at the individual article/chapter/item level, the most granular report type.

Metric types

Rather than a single generic “usage” count, COP5 defines a controlled vocabulary of Metric_Types grouped into broad activity categories — Searches, Investigations, Requests, and Access_Denied. Two of the most commonly cited in renewal and cost-per-use analysis are:

Total_Item_Requests — the total count of requests for full content (e.g. every full-text download), including repeat requests for the same item by the same user within the standard deduplication window.
Unique_Item_Requests — the count of requests for full content after COP5’s double-click deduplication rule collapses repeated requests for the same item by the same user in short succession into a single count, giving a closer approximation of distinct usage events.

By definition, Unique_Item_Requests can never exceed Total_Item_Requests for the same title and period — COUNTER’s own validator flags a report where that relationship is violated as non-compliant.

How reports are delivered: the COUNTER API (SUSHI)

Libraries can download COP5 reports manually from a vendor’s admin portal, but most electronic resource management (ERM) systems instead retrieve them automatically through the COUNTER API, the current name for what was originally called SUSHI (Standardized Usage Statistics Harvesting Initiative). This lets a library or consortium harvest COUNTER 5 reports from many vendor platforms on a schedule, rather than staff logging into each platform separately.

Related standards

COUNTER 5 is one of several complementary library-metadata and usage standards that, together, support electronic-resource management. KBART (Knowledge Bases And Related Tools), also a NISO-recognized recommended practice, standardizes the title-level holdings metadata (ISSNs, coverage dates, embargo periods) that knowledge bases and link resolvers exchange — a different problem from COUNTER 5’s usage-reporting focus, but the two are frequently used together in the same electronic-resource management workflow: KBART tells a system what a library holds and for what date range, while COUNTER 5 reports how much of it was actually used.

Frequently asked questions

What replaced COUNTER 4?

COUNTER 5 (COP5) replaced COUNTER 4, with COP5 compliance required of report providers from January 2019. Release 5.1, a further refinement of COP5, became the required compliance baseline from January 2025.

Is COUNTER 5 the same as SUSHI?

No. COUNTER 5 (COP5) is the reporting standard — it defines what a compliant usage report contains. SUSHI, now called the COUNTER API, is a transport mechanism for retrieving those reports automatically rather than downloading them by hand; a library can technically receive COP5-compliant reports without using the API at all.

Who is COUNTER 5 compliance relevant to?

Primarily publishers, aggregators, and other content platforms, who must produce compliant reports to be listed on the COUNTER Registry, and the libraries and consortia who consume those reports to make evidence-based collection-development, cost-per-use, and renewal decisions.

Use in your systems

JATS XML <role> element

xml

<role vocab="credit"
      vocab-identifier="https://casrai.org/dictionary/"
      vocab-term="COUNTER 5"
      vocab-term-identifier="https://casrai.org/dictionary/term/counter-5" />

Schema.org DefinedTerm (JSON-LD)

json

{
  "@context": "https://schema.org",
  "@type": "DefinedTerm",
  "@id": "https://casrai.org/dictionary/term/counter-5",
  "name": "COUNTER 5",
  "identifier": "https://casrai.org/dictionary/term/counter-5",
  "description": "COUNTER 5 (formally the COUNTER Code of Practice, Release 5, or 'COP5') is the current international standard governing how publishers, aggregators, and other content platforms must record and report usage statistics — searches, investigations, and requests — for the electronic resources (journals, databases, books, and multimedia items) they license to libraries and consortia. A usage report qualifies as 'COUNTER 5 compliant' only if it is produced from one of COP5's defined Master Report templates, uses COP5's controlled Metric_Types vocabulary, applies COP5's double-click and robot-filtering deduplication rules consistently, and (where automated) is retrievable via the COUNTER API (formerly called SUSHI, the Standardized Usage Statistics Harvesting Initiative). The standard exists so that a usage number from one publisher platform means the same thing as the equivalent number from another, letting libraries compare cost-per-use and make collection-development and renewal decisions on a like-for-like basis.",
  "inDefinedTermSet": "https://casrai.org/dictionary/domain/publishing#set",
  "url": "https://casrai.org/dictionary/term/counter-5",
  "sameAs": [],
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "publisher": {
    "@id": "https://casrai.org/#organization"
  },
  "dateModified": "2026-07-23T07:27:49",
  "inLanguage": "en"
}