LanguageTool vs Slack: Which One Does Your Team Actually Need?

LanguageTool is a grammar and style checker; Slack is a team messaging app. They solve different problems, but if you're trying to figure out which tool to budget for, here's the real breakdown.

Updated 2026-10 · 2026

LanguageTool

AI-powered grammar, style, and spell checker

Free / $19.92+user/month

Strengths

+Grammar, spelling, and style checking in 30+ languages
+Browser extension, desktop app, and MS Word/Google Docs add-ons
+Built-in paraphrasing and rewording suggestions

Weaknesses

-Does nothing for team messaging, file sharing, or calls
-Occasional false positives on style suggestions
-Full feature set requires a paid Premium plan

Best for

Writers, editors, and teams that need accurate grammar and style checking across emails, docs, and web forms

Slack

Team messaging and collaboration hub

Free / $7.25+user/month

Strengths

+Real-time channels, DMs, and huddles for team communication
+2,600+ app integrations (Google Drive, Zoom, Asana, etc.)
+Unlimited searchable message history on paid plans

Weaknesses

-Free plan caps message history at 90 days
-No built-in grammar or writing assistance
-Can get noisy and distracting without channel discipline

Best for

Teams that need a central place to chat, share files, and connect their other work tools

Feature Comparison

Feature	LanguageTool	Slack
Grammar & spell checking	Yes, 30+ languages	No
Team channels & DMs	No	Yes
Browser extension	Yes	No
Voice/video calls	No	Yes (huddles)
Third-party integrations	Google Docs, MS Office, browsers	2,600+ apps
File sharing	No	Yes
Free plan available	Yes, limited checks/day	Yes, 90-day history
API access	Yes (paid tiers)	Yes
Mobile app	Yes, with keyboard app	Yes
Writing style suggestions	Yes	No
Workflow automation	No	Yes (Workflow Builder)

The Verdict

These aren't competing products — LanguageTool fixes your writing, Slack moves your conversations. If you're comparing them because of budget, most small teams actually need both: Slack's free tier for chat and LanguageTool's free or low-cost checker for anything you write in it. Don't cut one to afford the other unless your team genuinely doesn't write much or doesn't need real-time chat.

How to switch from LanguageTool to Slack

1Export your LanguageTool personal dictionary from Settings > My Dictionary as a .txt file, and request a GDPR data export (JSON) from your account's privacy settings if you need a backup of saved corrections and usage history.
2Decide whether to keep or cancel your LanguageTool Premium subscription — Slack doesn't replace grammar checking, so most teams keep both rather than switching away entirely.
3Create a Slack workspace at slack.com and invite your team using their work email addresses or a shared invite link.
4Set up channels that mirror your current workflows (e.g., #content-review, #announcements) instead of relying on email threads.
5Reconnect your writing tools by installing the LanguageTool browser extension so it still checks your text inside Slack's web app, since there's no native Slack integration.
6Migrate any shared style guides or writing checklists into a pinned message or Slack Canvas so the team has a single reference point.

LanguageTool vs Slack: common questions

How do I export my data from LanguageTool before switching tools?+

Go to your LanguageTool account settings and export your personal dictionary (My Dictionary > Export) as a .txt file. If you need a full record of your account data, request a GDPR data export from the privacy settings page, which LanguageTool sends as a downloadable file within a few days.

What do I lose if I drop LanguageTool and only use Slack?+

You lose grammar, spelling, and style checking entirely — Slack has no native writing assistance. If your team writes a lot of external-facing copy (emails, proposals, docs), you'll want to keep a grammar checker running alongside Slack, even a free one.

Is Slack's free plan enough for a small team?+

For teams under 10 people with light usage, yes — but the 90-day message history limit and 10-integration cap are the main pain points. Once you rely on searching old conversations or connecting more than a handful of apps, you'll likely need Slack Pro at $7.25/user/month.

Does Slack integrate with LanguageTool or other grammar checkers?+

Slack doesn't have a native LanguageTool integration, but LanguageTool's browser extension works inside Slack's web app since it checks text in any editable field. There's no first-party Slack app for it in the Slack App Directory as of now.

How does the cost compare over a year for a 10-person team?+

LanguageTool Premium runs roughly $19.92/user/month billed monthly (cheaper annually, around $5-6/user/month), so a 10-person team pays several hundred to a couple thousand dollars a year depending on the plan. Slack Pro at $7.25/user/month comes to about $870/year for 10 users — and since they serve different purposes, most teams end up paying for both, not choosing one.