OnlyOffice

Microsoft 365 capability without the Microsoft 365 dependency

Google Workspace and Microsoft 365 are dominant office productivity platforms. They are also subscription services where your documents live on a vendor's infrastructure, where collaboration happens in a system you do not control, and where every seat costs a monthly fee that increases on the vendor's schedule. OnlyOffice is the open source office productivity suite that gives your organisation real-time collaborative document, spreadsheet and presentation editing, with full Microsoft Office format compatibility, running on infrastructure you control. Organisations across Europe, including those with the most stringent data sovereignty requirements, choose OnlyOffice because it answers a question that Microsoft and Google cannot: where exactly is our data, and who can access it? Node deploys and manages OnlyOffice as a fully managed service on your infrastructure.

What OnlyOffice is

OnlyOffice is a feature-complete open source office productivity suite comprising three core editors: Documents (word processing), Spreadsheets and Presentations. The editors handle Microsoft Office formats natively, support real-time collaborative editing, and provide the features that professional users expect from an office suite.

OnlyOffice is not a simplified web-based alternative. It is a high-fidelity office suite that renders complex Word documents, Excel workbooks and PowerPoint presentations accurately, preserving formatting, formulas, macros and layout with a fidelity that makes it the choice for organisations that cannot afford compatibility problems with partners and clients using Microsoft Office.

OnlyOffice is deployed at scale by organisations for whom data residency is non-negotiable: European public sector organisations, legal and professional services firms with client data obligations, healthcare organisations with regulatory requirements, financial services businesses with data governance requirements, and enterprises that have decided that business productivity data belongs on their infrastructure, not in a vendor's cloud.

The platform is used by over 10 million users globally and is trusted by major enterprises and government organisations. It is actively developed, with regular releases incorporating new features and format compatibility improvements.

Document editor

OnlyOffice's document editor provides the complete word processing capability that professional users require, with full Microsoft Office format compatibility.

Microsoft Word compatibility: documents open and save in .docx format natively. Complex formatting, including tables, headers and footers, section breaks, footnotes, cross-references and tracked changes, is preserved accurately. A document created in Microsoft Word opens in OnlyOffice with correct layout and is returned to the Word user without compatibility issues.

Real-time collaboration: multiple users edit the same document simultaneously. Changes appear in real time for all collaborators. Presence indicators show which users are in the document and where their cursor is positioned. Co-authoring works the same way it does in Google Docs and Word Online, except on your own infrastructure.

Track changes and review: the review workflow familiar from Microsoft Word is fully supported. Authors submit documents for review, reviewers add tracked changes and comments, authors accept or reject changes, and the document converges on a final version with full history preserved.

Styles and templates: apply paragraph and character styles to maintain consistent document formatting. Create document templates with pre-defined styles, headers, footers and initial content. New documents based on templates inherit the organisation's formatting standards.

Mail merge: generate personalised documents from a data source. Contracts, letters, certificates and any other document that needs personalising at scale is produced from a single template with data-driven field substitution.

Document comparison: compare two versions of a document to produce a tracked-changes view of every difference. Useful for contract review workflows where versions from different parties need to be reconciled.

Spreadsheet editor

OnlyOffice's spreadsheet editor provides the full Excel-compatible capability that finance, operations and analytical teams require.

Excel format fidelity: .xlsx files open accurately with formulas, pivot tables, conditional formatting, named ranges, charts and data validation preserved. Workbooks created in Excel are opened by your team in OnlyOffice, modified and returned to Excel users without format degradation.

Formula library: the complete Excel formula library is supported, including financial, statistical, logical, lookup and reference, text and date functions. Complex nested formulas and array formulas work as expected.

Pivot tables: create and modify pivot tables for data analysis and summarisation. Filter, sort and group source data. Refresh from updated source ranges. Pivot table capability is fully implemented, not a simplified approximation.

Collaborative editing: multiple users work on the same spreadsheet in real time. Changes are visible immediately to all collaborators. User presence and cursor position are shown. Simultaneous editing of different sheets or different areas of the same sheet is handled without conflict.

Charts and visualisations: create the full range of Excel-compatible chart types (bar, line, pie, scatter, combination and others) with formatting options that transfer correctly when the file is opened in Excel.

Data validation: define validation rules for cells and ranges that restrict input to specified types, ranges or list values. Validation rules created in Excel are preserved and enforced in OnlyOffice.

Presentation editor

OnlyOffice's presentation editor provides PowerPoint-compatible slide creation and editing for your team's presentation requirements.

PowerPoint compatibility: .pptx files open accurately with slide layouts, animations, transitions, embedded media, speaker notes and custom themes preserved. Presentations created in OnlyOffice are opened in PowerPoint by recipients without layout or formatting issues.

Collaborative presentation editing: teams work on presentations simultaneously in real time. Multiple team members contribute slides to a deck concurrently. The presentation is available to the entire team for editing as soon as it exists: no "checking out" a file, no emailed revisions.

Slide master and themes: apply consistent branding through slide masters and theme definitions. Organisation presentation templates with corporate colours, fonts, logo placement and layout standards are created once and applied across the team.

Presenter mode: deliver presentations directly from OnlyOffice with presenter view showing speaker notes, a slide preview and presentation timer. No need to export to PowerPoint for delivery.

Forms and PDF capabilities

OnlyOffice includes form creation and PDF handling that extends the productivity suite beyond traditional office documents.

Form creation: create fillable forms in .docxf format with text fields, dropdown selectors, checkboxes and date pickers. Distribute forms for completion and collect structured input data. Forms can be protected so that recipients can fill in the fields but cannot modify the underlying document structure.

PDF editing: annotate, comment on and add form fields to PDF documents directly within OnlyOffice. For organisations that receive PDFs and need to mark them up or extract information from them, PDF handling within the same suite removes the need for a separate PDF tool.

Integration with Nextcloud

OnlyOffice integrates natively with Nextcloud Private Cloud. When both platforms are deployed together, files stored in Nextcloud open directly in OnlyOffice for editing with a single click. Users save back to Nextcloud from within the editor. Version history in Nextcloud reflects every save from the OnlyOffice editor.

This combination (Nextcloud for file storage, synchronisation and sharing; OnlyOffice for collaborative editing) provides the complete self-hosted equivalent of Microsoft 365 or Google Workspace, on infrastructure you control, with no per-seat fees from either vendor.

Keycloak integration and enterprise identity

OnlyOffice Docs integrates with Keycloak via OAuth 2.0 or SAML 2.0 for single sign-on. Users access the document editing interface with their corporate credentials. MFA requirements and session policies enforced by Keycloak apply consistently to document access. Group membership in Keycloak can drive access permissions to shared document spaces.

Deployment options

Document Server: the OnlyOffice Docs server is the core editing engine, deployed as a containerised service on Node's infrastructure or your own. The Document Server is accessed through the web interface or through integrations with Nextcloud, SharePoint, Confluence or other platforms.

DocSpace: OnlyOffice DocSpace, the current collaboration product, organises documents into rooms with granular permissions for internal teams and external collaborators. For organisations that want a single self-hosted document collaboration platform alongside the editors, DocSpace provides a more complete solution.