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Preview of MerciApp

MerciApp by MerciApp

Write better, faster, wherever you work.

4.2 (33 reviews)4.2 (33 reviews)
2,916 Users2,916 Users
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The AI writing assistant serving modern teams.Write better and faster with AIAutocorrection that saves you a lot of timeSet the tone by creating your own AI assistantsStandardize what comes backSmart spellchecking, right when you need itA library of AI asssitants to save timeThe result of 30 years of research, carried out by our team of linguistic experts
About this extension
⇒ <strong>Terms of Use</strong>

By installing the extension, you agree to the Terms of Use(https://www.merci-app.com/en/gtu) and acknowledge that you have read the Cookie Policy (https://www.merci-app.com/en/cookies-policy).



MerciApp helps you correct, rephrase, and structure your writing instantly, right inside your browser. From emails and CRMs to messaging apps and collaborative tools, it improves your texts and speeds up repetitive replies without disrupting your workflow.



Correct • Professional real-time autocorrect

More than just a spelling and grammar checker, MerciApp enhances the clarity, conciseness, and tone of your messages. Every suggestion comes with a clear explanation, so you understand the correction and keep improving.

What MerciApp detects:

• Spelling mistakes and homophones (“I should of —> I should have ”)
• Complex agreement rules, verb conjugations, and infinitive vs. past participle confusion
• Overly long sentences, missing punctuation, excessive use of abbreviations
• Contextual errors (capitalization, dates, consistency)

Corrections appear as you type. No copy and paste. No interruptions.



Transform • Rewriting and built-in AI assistants

Reword, structure, or translate your text without leaving the tool you are using. Create custom assistants for meeting summaries, standard support replies, sales pitches, and more. Share them with your team to keep communication consistent and aligned.

In practice:

• Select a passage and request a clearer, more direct, more formal rewrite, or a structured summary
• Set up business assistants, for example “turn my notes into a customer report,” and reuse them in just two clicks
• Instantly translate an email into English, Spanish, German, and more, directly from the interface



Expand • Smart snippets: reply in two seconds without copying and pasting

Expand allows you to create reusable snippets: standard replies, signatures, greetings, product explanations, etc.

Type a shortcut (e.g. /acknowledgment) → MerciApp instantly inserts “We have received your message and will get back to you within 24 hours.”

Dynamic snippets: customize your templates with variables (customer first name, date, order reference, etc.) to save time without losing personalization.

Share your snippets with your team to keep support, sales, and administrative responses consistent and on-brand.



Works wherever you write

Gmail, Outlook, Salesforce, HubSpot, Slack, Teams, Notion, LinkedIn... MerciApp works seamlessly with your everyday tools. Correction and AI assistants are available with a single click, wherever you need them.

Automatic language detection ensures MerciApp only corrects the language you’re writing in: English, Spanish, or others. The interface stays discreet, suggestions appear in context, and your workflow remains uninterrupted.



Designed for teams

• Corporate dictionary: add your business terms, acronyms, product names
• Shared rules: harmonize tone, formulas, and writing standards
• Snippets and team assistants: centralize updates to your tools.
• Centralized management: access rights, usage tracking, configurable and shareable assistants

Ideal for sales teams, customer support, account management, internal communications, and much more.



Reliability & Compliance

MerciApp is built on 30 years of linguistic research and a dictionary of over 500,000 entries. Trusted by thousands of B2B users, it is recognized for its accuracy and full GDPR compliance.

A French alternative to Grammarly, crafted to meet professional standards.



Install and get started
  1. Add the extension to Chrome
  2. Create your account (30-day free trial)
  3. Start writing: MerciApp corrects and improves in real time
Rated 4.2 by 33 reviewers
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Permissions and data

Required permissions:

  • Get data from the clipboard
  • Input data to the clipboard
  • Monitor extension usage and manage themes
  • Access browser tabs
  • Access your data for all websites
Learn more
More information
Add-on Links
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Version
3.83.0
Size
4.09 MB
Last updated
5 days ago (Feb 24, 2026)
Related Categories
  • Language Support
  • Social & Communication
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