WProofreader SDK & API

Multilingual spelling & grammar checker with AI writing assistance

Demo text size is limited to 2000 characters.

Writing solutions across industries

Find out how WProofreader can help with writing and spellchecking tasks in your field. For industries that handle sensitive information, WProofreader allows your organization to maintain control over its data.

WProofreader provides medical proofreading for healthcare domain.

Healthcare

Use specialized medical and veterinary dictionaries with Tall Man Lettering support to check patient records, medication reports, orders, clinical notes, labels, and other healthcare content.

WebSpellChecker offers proofreading capabilities for educational institutions.

Education

Support writing across LMSs and assessment platforms, from student assignments and test responses to course materials and everyday academic communication.

WProofreader offers embedded text correction for the financial sector.

Banking and finance

Keep sensitive text processing secure across internal applications and CMSs for banking, insurance and risk management documentation

WebSpellChecker offers proofreading capabilities for Legal institutions.

Legal

Specialized legal dictionaries help check terminology across contracts, agreements and other legal documents, while style rules keep language consistent.

More than a proofreading tool

Built for businesses and organizations that need reliable writing support backed by human expertise. Give your users real-time spelling and grammar checking with AI-powered tools for rewriting and refining text.

Multilingual text checker

WProofreader is a multilingual spelling, grammar and style checker. 80+ languages. AI-driven suggestions are available for English, German and Spanish.

Deployment & Security

Choose cloud or on-premises deployment to meet your organization's infrastructure and security requirements. Keep your data protected during processing with TLS-encrypted transmission and additional safeguards.

AI writing assistant

Rewrite, improve, summarize, expand, or shorten text in multiple languages using predefined prompts. No AI watermarks are added to edited text, giving your users flexibility in how they use their content.

All-in-one writing support

Cover everyday text checking and more advanced writing needs in one solution. Use real-time spelling and grammar suggestions, autocorrect and autocomplete features, organization-wide and user dictionaries alongside the Style Guide Builder for your team. The AI Writing Assistant adds options for rewriting, summarizing and adjusting your text.

WProofreader core features set.
WProofreader customization options: language settings, UI themes and localizations, custom dictionaries.

Flexible configuration

Customize the WProofreader JavaScript component: set the primary language and UI localization, manage settings and personalize the interface with built-in or custom themes.
Our technical team will help your business or organization integrate and configure WProofreader for your needs.

Accessibility standards

WProofreader is regularly tested for accessibility and meets the majority of WCAG 2.1 Level A and AA success criteria. Keyboard navigation helps users with different abilities access key features.

WProofreader keyboard navigation and color contrast accessibility features.
WProofreader API request example.

Standalone API

Use the standalone WProofreader API when you need more control over how text checking is integrated into your product or system. Build your own workflow and use WProofreader capabilities without the predefined UI.

Product updates and support

WProofreader receives regular product improvements, linguistic updates and security fixes. For technical or sales questions, our team responds within one business day.

WebSpellChecker team responds within a business day to all sales and tech requests and provides guided installation in case it’s needed.

Integrate with your platform

Integrate WProofreader with popular RTEs, CMSs and custom web applications using ready-to-use plugins, the JavaScript component or standalone API.

CKEditor 5 is a powerful, modern editing framework with a modular architecture and collaborative features that lets developers build feature-rich content editors tailored to their needs.
CKEditor 4 is a proven, reliable WYSIWYG editor trusted by millions worldwide, offering robust features and extensive customization options for creating rich content experiences.
TinyMCE is a flexible, feature-rich WYSIWYG editor that empowers developers with extensive customization capabilities while delivering an intuitive editing experience users love.
Froala is a WYSIWYG Editor is a beautiful JavaScript web editor that's easy to integrate for developers and your users will fall in love with its clean design.
Tiptap is a headless, framework-agnostic editor toolkit that gives developers complete control to build custom editing experiences with modern JavaScript and a flexible API
Quill is a modern WYSIWYG editor built for the web with an API-driven architecture that allows developers to customize and extend functionality while maintaining a clean, intuitive interface.
Syncfusion Rich Text Editor is a powerful, enterprise-grade WYSIWYG component with comprehensive formatting tools and seamless integration into the Syncfusion UI suite for consistent user experiences.
HTML controls are classic editable elements like <textarea>, <element contenteditable=”true” and “false”>, <textarea readonly>

Don't see your editor or platform? let us know to check compatibility with your setup.

What’s inside WProofreader SDK?

Integrate pre-built JavaScript libraries into HTML elements, WYSIWYG editors, CMS or use an off-the-shelf extension to season your apps and systems with proofreading & rewording functionality. Build and go!

WPrrofreader SDK — combo of pre-built components for WYSIWYG editors such as CKEditor, Froala, TinyMCE, Quill.js, and standalone HTTP API helping development teams enrich web apps and custom systems with proofreading and rewording functionality

RTEs and HTML editable controls

The component integrates in HTML editable controls and rich text editors within web applications to scale them up with multilingual proofreading and paraphrasing functionality.

WProofreader plugin for CKEditor 5 — the multilingual spelling and grammar checking solution for CKEditor 5. It provides both instant and in-dialog proofreading modes in a convenient UI.

CKEditor 5 plugin

The multilingual CKEditor 5 spell and grammar check plugin. It provides both instant and in-dialog proofreading modes in a convenient UI.

WProofreader plugin for TinyMCE — the plugin adopts the full functionality of the WProofreader component, with minor adjustments to the editor's appearance and features.

TinyMCE plugin

The TinyMCE spell check plugin adopts the full functionality of the WProofreader component, with minor adjustments to the editor's appearance and features.

WSC Web API — grammar and spell check functionality of your application with WProofreader HTTP API.

Standalone API

Standalone WProofreader API empowers developers to tweak, twist, extract, manipulate and further integrate proofreading capabilities into unique web systems.

WProofreader Plugin for Drupal CMS.

WProofreader for Drupal

The CKEditor 5 Plugin Pack includes a free limited and full version of WProofreader, a grammar and spell checker.

SCAYT plugin for CKEditor 4 — Out-of-the-box multilingual grammar and spell checker plugin for CKEditor 4 instantly detects and underlines writing issues in as-you-type mode.
legacy

SCAYT plugin for CKEditor 4

Out-of-the-box multilingual grammar and spell checker plugin for CKEditor 4 instantly detects and underlines writing issues in as-you-type mode.

Pricing

Choose a plan based on your text processing volume, team size and product needs. For higher usage or specific security and deployment requirements, contact sales team.

Free

€0
€0

For getting started with WProofreader on a small scale.
‍

Basic spelling, grammar, style with daily word limit

Multiple languages support

User-level custom dictionary

WProofreader branding

Public product documentation

Free

€0
€0

For getting started with WProofreader on a small scale.
‍

up to 20,000 words processed per day

up to 20,000 words processed per day

Basic spelling, grammar, style with daily word limit

Multiple languages support

User-level custom dictionary

WProofreader branding

Public product documentation

Public product documentation

Free

€0
€0

For getting started with WProofreader on a small scale.
‍

Basic spelling, grammar, style with daily word limit

Multiple languages support

User-level custom dictionary

WProofreader branding

Public product documentation

Growth

€34
/ month
€340
/ year

For smaller teams and products with moderate text processing needs.
‍

Multilingual text check

Autocorrect and autocomplete suggestions

Custom dictionaries

(up to 3)

Style guide builder

(up to 1 collection)

Team access

(up to 3 members)

Text operations within AI writing assistant (daily limit)

Growth

€34
/ month
€340
/ year

For smaller teams and products with moderate text processing needs.
‍

Up to 10 million words processed

Up to 120 million words processed

Multilingual text check

Autocorrect and autocomplete suggestions

Custom dictionaries

(up to 3)

Style guide builder

(up to 1 collection)

Team access

(up to 3 members)

Team access

(up to 3 members)

Text operations within AI writing assistant (daily limit)

Growth

€34
/ month
€340
/ year

For smaller teams and products with moderate text processing needs.
‍

Multilingual text check

Autocorrect and autocomplete suggestions

Custom dictionaries

(up to 3)

Style guide builder

(up to 1 collection)

Team access

(up to 3 members)

Scale

€62
/ month
€620
/ year

For growing products and teams with higher text processing volumes.
‍

Custom dictionaries

(up to 15)

Style guide builder

(up to 3 collections)

Team access

(up to 15 members)

Everything in Growth plan

Scale

€62
/ month
€620
/ year

For growing products and teams with higher text processing volumes.
‍

Up to 25 million words processed

Up to 300 million words processed

Custom dictionaries

(up to 15)

Style guide builder

(up to 3 collections)

Team access

(up to 15 members)

Everything in Growth plan

Scale

€62
/ month
€620
/ year

For growing products and teams with higher text processing volumes.
‍

Custom dictionaries

(up to 15)

Style guide builder

(up to 3 collections)

Team access

(up to 15 members)

Everything in Growth plan

Enterprise

Custom
Custom

For organizations with higher usage, custom requirements, or self-hosted deployment.

Everything in Scale

Custom word volume, including unlimited usage for self-hosted

Flexible dictionaries, style guides, and team limits

Cloud or self-hosted deployment

Custom payment terms

Custom contract terms and redlines

Priority support

Dedicated account manager

Enterprise

Custom
Custom

For organizations with higher usage, custom requirements, or self-hosted deployment.

Everything in Scale

Custom word volume, including unlimited usage for self-hosted

Flexible dictionaries, style guides, and team limits

Cloud or self-hosted deployment

Custom payment terms

Custom payment terms

Custom contract terms and redlines

Enterprise

Custom
Custom

For organizations with higher usage, custom requirements, or self-hosted deployment.

Everything in Scale

Custom word volume, including unlimited usage for self-hosted

Flexible dictionaries, style guides, and team limits

Cloud or self-hosted deployment

Custom payment terms

Need a personal writing assistant?

Use WProofreader directly in your browser to check spelling, grammar and writing style as you type. Write confidently in multiple languages across the web.

Multilingual AI grammar checker and text rewriter by WProofreader

Frequently asked questions

Can I use WProofreader for free?

Yes. You can start with the WProofreader Free Plan and upgrade when you need higher usage limits and more advanced features. Before choosing a paid cloud plan, you can explore its full capabilities with a 14-day free trial. A 30-day evaluation period is also available for the on-premises version. The WProofreader Browser Extension is free for personal use, while the Business version is available with a premium subscription.

What’s the difference between cloud and on-premises deployment?

The cloud version is the easiest way to start. We host everything for you on AWS servers in the US East region, so you don’t need to manage any infrastructure. You simply integrate the frontend while we handle the backend. 

The on-premises solution provides full control and keeps all data within your own infrastructure, making it ideal for organizations with strict security or compliance needs. This option supports various operating systems, including Windows Server and multiple Linux distributions, and is compatible with virtualization and containerization technologies. Each release undergoes extensive testing to ensure smooth deployment and optimal performance across diverse environments, including compatibility with web servers like NGINX and Apache, and proper JVM configuration.

Both options prioritize security with regular updates and thorough testing to ensure smooth operation. While the cloud uses powerful GPUs for AI tasks, the on-premises solution is optimized for efficient performance on standard CPU hardware.

What’s the difference between WProofreader SDK and the Browser Extension?

WProofreader SDK is designed for developers and teams who want to build proofreading directly into their web apps, editors, or custom workflows. It works well with popular WYSIWYG editors like CKEditor or TinyMCE, or as a standalone API. You can choose cloud hosting or deploy it on your own servers for extra control.

WProofreader browser extension is better suited for individual users or teams who need an out-of-the-box spelling and grammar check in their browsers. It works anywhere you write online: emails, CRMs, or web forms. Use it for free through our cloud or switch to the Business plan to host it on your own servers.

What happens if I exceed my plan limits?

If you go over your word limit, the service will pause until you add more capacity. Don’t worry, our team keeps an eye on your usage and will notify you in advance if you’re getting close. This way you’ll have time to upgrade or buy extra words.

We’ll help you pick the best option based on how much your team actually uses. We also offer discounts for high-volume needs, so if you expect big spikes, just let us know, and we’ll work out the best plan for you.

Which integrations does WProofreader support?

WProofreader supports popular WYSIWYG Editors, CMSs and learning management systems, including CKEditor 5, TinyMCE, Froala, Quill, Drupal, WordPress and Moodle. For custom web applications and systems, you can integrate WProofreader using the JavaScript component or standalone API.

See all supported integrations

How does WProofreader handle my data?

Texts sent to WProofreader aren't collected for further use. In the cloud version, data in transit is protected with TLS 1.3 and the service is hosted on AWS infrastructure. If your organization requires greater control over data processing, WProofreader can also be deployed on-premises, keeping processing within your own infrastructure. For more details, see our Security Center or request the security whitepaper.

Can’t find the answer you’re looking for? Please chat to our team.