Tolgee — Developer-Friendly Localization Platform

Introduction

Tolgee is an open-source localization platform designed to bridge the gap between developers and translators. It provides a web-based translation management UI, SDKs for major frontend frameworks, and an in-context editing feature that lets translators click on text directly in the running application to edit translations.

What Tolgee Does

• Manages translation strings for multiple languages in a web dashboard with search, filters, and screenshots
• Provides in-context editing: translators click text in the live app to translate without touching code
• Integrates with React, Vue, Angular, Svelte, and vanilla JS via native SDKs
• Supports machine translation via DeepL, Google Translate, and AWS Translate
• Imports and exports translations in JSON, XLIFF, PO, and Android/iOS resource formats

Architecture Overview

Tolgee is a Spring Boot application with a PostgreSQL database for translation storage. The web UI is built with React and Material UI. The SDKs wrap the Tolgee REST API to fetch translations at runtime or build time. In development mode, the SDK injects an overlay that highlights translatable strings and opens the translation editor on click. For production, translations are bundled statically or fetched from the Tolgee CDN.

Self-Hosting & Configuration

• Deploy with Docker using a single container or Docker Compose with PostgreSQL
• Configure via environment variables: tolgee.postgres-autostart.enabled, tolgee.authentication.*, SMTP settings
• Set up machine translation by adding API keys for DeepL or Google Translate in the admin panel
• Integrate the Tolgee SDK into your frontend project for automatic key synchronization
• Use the CLI (@tolgee/cli) to push/pull translations between your codebase and the Tolgee server

Key Features

• In-context translation editing directly in the running application during development
• Screenshot-based context: screenshots are attached to keys so translators see where text appears
• Translation memory and glossary for consistency across projects
• Batch operations with AI-assisted translation suggestions
• Granular permissions with project-level roles for developers, translators, and reviewers

Comparison with Similar Tools

• Weblate — Mature localization platform with Git integration; more focused on open-source project workflows
• Crowdin — Commercial localization platform; SaaS-first with a free tier for open source
• Lokalise — Enterprise localization SaaS; no self-hosted option
• Traduora — Simple open-source translation management; fewer integrations and no in-context editing
• Pontoon — Mozilla's localization tool; focused on Firefox and Mozilla projects

FAQ

Q: Can I use Tolgee in production without the SDK? A: Yes. Export translations as static JSON files and bundle them with your app. The SDK is optional for production.

Q: Does Tolgee support plurals and ICU message format? A: Yes. It supports ICU message format including plurals, selects, and nested arguments.

Q: How do I migrate from i18next or react-intl? A: Import your existing JSON or XLIFF files into Tolgee, then swap the i18n provider in your app to use the Tolgee SDK.

Q: Is there a free cloud-hosted version? A: Yes. Tolgee Cloud offers a free tier with limited seats. Self-hosting is free and unlimited.

Sources

• https://github.com/tolgee/tolgee-platform
• https://tolgee.io