Arelle

Arelle is a free, open-source platform for validating and processing XBRL, a standard for structured business data. It is available as a desktop application, command-line interface, Python API, Docker image, and web service. Supported formats and standards include XBRL 2.1, XBRL Dimensions, Inline XBRL, xBRL-JSON, and xBRL-CSV. Filing-rule support covers programs such as ESMA ESEF, SEC EDGAR, US FERC, Japan EDINET, and South Africa CIPC. The Web Service API can connect with applications including Excel, Java, and Oracle. An extensible plugin architecture supports custom validation and data-processing rules. Desktop builds are available for Windows, macOS, and Linux, and the Docker image can serve local validation or an HTTP service. Arelle is released under the Apache License 2.0. Community plugins come with desktop builds and the full Docker image, but Python package and source installations need plugins added and configured separately. Its built-in web server has no authentication or authorization and is intended for trusted callers, not public internet or multi-tenant use.

Arelle offers multiple ways to validate and process XBRL, with support for filing rules and custom plugins. Treat its built-in web server as a trusted-caller service rather than a public or multi-tenant endpoint.

Arelle suits regulators, software providers, auditors, and filers who need a standards-based tool for structured business data. Developers can also use its APIs and plugins to connect or customize validation workflows.

Overview

Arelle is a free, open-source XBRL validation and processing platform for teams that need to work with structured business reports. It suits filers, auditors, regulators, and software providers who want deployment and interface choices without a software fee. Its strongest case is standards-based validation; it is not a tool for submitting filings to regulators.

Key features

Arelle handles XBRL 2.1, XBRL Dimensions, Inline XBRL, xBRL-JSON, and xBRL-CSV. That range makes it relevant to organizations working with different XBRL formats, while support for filing rules across 10 jurisdictions—including ESMA ESEF, SEC EDGAR, US FERC, Japan EDINET, and South Africa CIPC—gives filers a basis for checking reports against program requirements. Validation is useful before filing, but the product does not transmit submissions to regulators.

Teams can use the desktop application, command line, Python API, Docker image, or web service. This is a practical advantage for mixed workflows: individuals can work in a desktop build, while developers can script processing or run it in a container. The Web Service API can integrate with applications such as Excel, Java, and Oracle. An extensible plugin system also allows custom validation and data-processing rules, though Python-package and source installs require users to add and configure plugins themselves. Desktop builds and the full Docker image include community plugins.

The built-in web server is for trusted callers only: it has no authentication or authorization, so it is unsuitable for public internet exposure or multi-tenant service. For teams that need a web endpoint, that security boundary is a deployment constraint, not a minor configuration detail. Arelle is released under Apache License 2.0. Support channels include GitHub issues, a Google Group, and support email; problems inside third-party products should go to those product developers.

Pricing

Arelle’s free plan costs nothing and includes the open-source platform, desktop builds, Python package, Docker image, and community plugins. It includes XBRL support, validation rules, API access, and on-premises deployment, with no free trial. The zero price makes it a credible option for teams able to manage deployment and configuration themselves; the main tradeoff is that plugin setup can fall to users of package and source installations. Its free access does not include regulator submission.

Platforms

Official desktop builds are available for Windows, macOS, and Linux. Arelle also supports API use and self-hosted deployment, with Docker available for local validation or an HTTP service. These options favor organizations that want control over where processing runs, rather than buyers seeking a hosted web product.

Who it's for

Arelle is a strong fit for filers and auditors who need to validate XBRL against filing rules, and for software providers that want an API, plugins, or a self-hosted processing component. Regulators are also within its intended audience. Organizations seeking a managed submission workflow or a publicly exposed multi-tenant validation service should look elsewhere or provide a separate, secured architecture.

Pros and cons

• Pro: Broad format and filing-rule coverage makes one free platform useful across varied XBRL workflows and 10 jurisdictions.
• Pro: Desktop, command-line, API, Docker, and web-service interfaces give technical teams several ways to fit processing into existing operations.
• Pro: Apache 2.0 licensing and an extensible plugin architecture suit organizations that need to adapt validation or processing.
• Con: Arelle validates and processes but does not submit filings, so filing teams need a separate submission route.
• Con: The built-in server lacks authentication and authorization, ruling it out as a public or multi-tenant endpoint without another security layer.
• Con: Python-package and source installations require separate plugin installation and configuration, adding maintenance work compared with bundled desktop or full Docker options.

Alternatives

For a broader comparison, see Regulatory Reporting Software. FIS Data Integrity Manager is a paid web-based alternative. REGREP is worth considering for buyers looking for a freemium API and web option, with paid plans including per-record-block TIN validation and annual FATCA service. CoreFiling Seahorse is a paid web alternative. Reg360 is another paid web option with pricing available upon request. Altova Regulatory Solutions offers a freemium option and a free trial, with its CbC Reporting App subscription starting at $999 a year per user. Complyfirst Regulatory Reporting uses custom proposals and may impose licence restrictions, fair data-usage limits, and separately priced premium features. LSEG Corporate Treasury Risk is a paid web product with pricing available by contacting sales. Regnology Abacus360 Banking is a paid self-hosted and web option with modular, configurable service options.

Verdict

Choose Arelle if your team needs free, standards-based XBRL validation and processing with options for desktop, code, or self-hosted deployment. Its format and filing-rule coverage, API access, and extensibility are compelling without a licence fee. Look elsewhere if you need regulator submission, or if you require a public or multi-tenant web service without building security around it.