4.1 / 5

Tone Check

Analyzes the tone of emails and posts before you send them

Useful

Privacy

The Problem

Written communication lacks tone cues, leading to misunderstandings and regret

Current Solutions (Not Great)

Re-read and guess, ask a colleague to review, Grammarly (tone is secondary feature)

Who Needs This

Professionals, managers, anyone who's sent an email they regretted, non-native speakers

You've written an email when frustrated and regretted sending it. Or you've agonized over whether a message sounds too aggressive, too passive, or too formal. Tone Check analyzes any text field—email composers, social media posts, Slack messages—and shows you how it might land before you hit send. It catches unintentional harshness, flags passive-aggressive patterns, and suggests rewrites. All locally, so your draft emails never leave your browser.

Honest Take

Grammarly already owns this space and has tone detection built in, but their privacy model is questionable—your emails go to their servers. Local-first tone analysis is genuinely valuable for sensitive work communications, though you'll need to nail the UI to avoid feeling naggy or intrusive.

Monetization Ideas

Ways to turn this into revenue

Freemium

Free basic, $5-15/mo for pro

Subscription

$5-29/month or $49-199/year

One-Time Purchase

$9-49 per license

Features

Key features that make this app valuable

Automatic tone analysis in text fields
Tone indicators (aggressive, passive, passive-aggressive, warm, cold)
Specific phrase highlighting with explanations
Rewrite suggestions per tone target
Confidence/assertiveness meter
Formality level detection
Recipient-appropriate suggestions (boss, peer, client)
History of sent message tones

Build Prompt

Use this prompt with an AI assistant to start building

Build a Chrome extension called 'Tone Check' using WebInfer. Manifest V3 with activeTab, storage permissions. Content script detects text inputs on Gmail, Outlook, LinkedIn, Twitter, Slack web. Inject subtle tone indicator icon near text field. On pause in typing (debounce 1s) or explicit check, analyze text. Use generateObject to return { overallTone: 'warm'|'neutral'|'cold'|'aggressive'|'passive-aggressive'|'passive', confidence: number, formality: 'casual'|'professional'|'formal', issues: [{ phrase: string, issue: string, perceived: string, suggestion: string }], assertiveness: number, emotionalLoad: 'low'|'medium'|'high', rewrites: { warmer: string, more_assertive: string, more_professional: string } }. Display as small popover: color-coded tone badge, expandable details. Click issue to see explanation and one-click replacement. Context menu 'Check tone of selection' for any text on any page. Optional: audience selector (manager, peer, customer) adjusts suggestions.

Score Breakdown

Pain