Online Tone Generator vs Superhuman

Tagline

Free browser-based utility to generate pure sine, square, triangle, and sawtooth audio tones

The fastest email experience, now with AI

Category

Pricing

Rating

Platforms

API

Open source

Description

An online tone generator that produces pure audio tones from 20 Hz to 20,000 Hz in real time. It operates entirely within the web browser using the Web Audio API, meaning it requires no downloads, installations, or user accounts, and can even work offline after loading. Users can generate sine, square, triangle, and sawtooth waveforms, perform frequency sweeps, execute left/right speaker balance tests, and use a community-inspired 165Hz water eject sound to help clear phone speaker grilles.

Superhuman uses AI to triage, summarize, and draft replies at keyboard speed.

Key features

• Generate pure tones from 20Hz to 20,000Hz
• Supports sine, square, triangle, and sawtooth waveforms
• Synthesizes audio locally in real time using the Web Audio API
• Frequency sweep generator tool for continuous low-to-high checks
• Speaker test tone generator with left, right, and center balance controls
• Water eject tool playing a 165Hz tone to help move trapped water from speaker grilles
• Download generated tones as a 5-second WAV file
• Share custom frequencies and waveforms via unique copied links
• Works offline after the page has initially loaded

• Token-aware generation
• Component variants
• Auto-layout

Pros

• Completely free to use with no account, sign-up, or registration required.
• Requires no installation or download, running entirely in the web browser.
• Runs locally on your device via the Web Audio API, keeping it functional offline after loading.
• Allows users to save the generated tone as a five-second WAV audio file.
• Enables sharing exact configurations through a copied custom URL link.
• Offers multiple wave types including sine, square, triangle, and sawtooth waveforms.
• Includes dedicated tools for frequency sweeps and left/right speaker panning tests.
• Features a community-inspired 165Hz water eject tool designed to help clear speaker grilles.

• Fastest keyboard-driven email
• AI-drafted replies
• Snippets and templates
• Send later and follow-up reminders
• Read receipts
• Split inbox
• Instant global search
• Polished, distraction-free UI

Cons

• No public API or developer integration documentation is provided on the site.
• Saved WAV audio files are limited to a fixed duration of five seconds.
• Browser security requires a manual user click to start sound playback.
• The water eject tool does not guarantee safety, physical speaker repair, or effectiveness.
• The utility cannot dry water inside the device or inside the charging connector.

• Expensive at $30/month
• Gmail and Outlook only
• Steep shortcut learning curve
• Requires onboarding call
• No family plan
• Limited mobile customization
• AI is a separate add-on cost
• Overkill for casual email users

Pricing plans

• StarterUSD25/month
  • • Superhuman AI
  • • Email Productivity
  • • Calendaring & Scheduling
  • • Support & Training
• BusinessUSD33/month
  • • Team Collaboration
  • • For Sales
  • • Team Administration
  • • Security
• Enterprise—
  • • All-in Enterprise Pricing
  • • Custom Compliance Needs
  • • Google Advanced Protection
  • • Advanced Admin Controls
• FreeUSD0
  • • AI chat unlimited while in beta
  • • Correctness suggestions
  • • Tone detection
  • • Limited prompts
• ProUSD12/month
  • • Unlimited AI chat
  • • Inline suggestions
  • • Paragraph translation in 17 languages
  • • Paragraph rewrites in 24 languages
• BusinessUSD33/month
  • • Everything included in Pro, plus:
  • • Ask AI
  • • Write with AI (voice and tone match)
  • • Team collaboration
• Enterprise—
  • • Everything included in Business, plus:
  • • Advanced security and admin controls
  • • Custom roles and permissions
  • • Dedicated support team

Website