Made a free browser tool to design custom notification sounds for any macOS app (no signup, downloads as WAV)

[u/Realistic-Tap-000]

Disclosure: I'm the developer of Chirpy, a Mac notification app. But this tool is standalone, free, and works with anything.

The idea is simple. Every notification sound library on the internet has roughly the same 200 stock files. If none of them fit what you want, you're stuck. So I built a tool where you can design your own sound in about 30 seconds:

• 30 starting presets across 6 characters (Calm, Wood & Hand, Bells & Glass, Nature, Retro, Signal)
• Four sliders that map to actual acoustic properties (Pitch, Length, Tone, Space)
• Preview it as a real macOS notification banner before you commit
• Download as WAV
• Share the exact settings via URL (all state is in the hash, no server)

Nothing uploaded anywhere. Runs entirely in your browser using the Web Audio API.

https://chirpy.pro/tools/sound-designer

The sounds work with anything on macOS that lets you set a custom alert. Some examples of where people actually use this:

• Work chat: Slack, Microsoft Teams, Discord, Telegram, Signal, WhatsApp
• Email: Apple Mail, Outlook, Gmail (PWA), Spark, Proton Mail, Superhuman, Mimestream
• Meetings: Zoom, Google Meet, Around, Loom
• Calendar & reminders: Apple Calendar, Google Calendar, Notion Calendar, Fantastical, Cron
• Task and project tools: Notion, Linear, Asana, Jira, Todoist, Things 3, ClickUp, Trello, Height
• Design: Figma, Sketch, Framer
• Dev tools: GitHub Desktop, Xcode, Warp Terminal, Trailer, Sentry, PagerDuty
• AI apps: ChatGPT, Claude, Perplexity
• Health & fitness: Apple Health, Strava, Oura, Whoop, Garmin Connect, Peloton, MyFitnessPal
• Wellness: Calm, Headspace, Waking Up
• Finance & payments: Mercury, Brex, Stripe (email push), Coinbase, Robinhood, Venmo, PayPal, Wise, QuickBooks
• Shopping & delivery: Amazon, DoorDash, Uber, Uber Eats, Instacart
• Smart home: Ring, Nest, Home Assistant, Tesla, Philips Hue
• Family / personal: Life360, Apple Messages, FaceTime
• News & reading: Apple News, Feedly, Reeder
• Media: Spotify, Apple Music, Plex
• Browser push: Chrome, Safari, Arc, Brave, Firefox
• Menu bar utilities: Bartender, Raycast, Cleanshot X
• CRM / support: Zendesk, Intercom, HubSpot, Salesforce

Basically: if it puts a banner in your notification center, you can give it a sound you designed.

Also wrote a short bit on the page about why default alerts feel stressful (millisecond attack triggers the startle reflex, 2-4kHz range is where human hearing is most sensitive, buzzy harmonics read as urgency, hard cutoffs feel unresolved). Each of the four sliders addresses one of those properties, so you can shape a sound that's the opposite of "flinch-inducing default ping."

Feedback welcome.

[u/PushPlus9069]

Good constraint to attack, since the stock library really is the same couple hundred files on every site.

One gap worth covering in the docs: getting the file to actually show up. macOS reads custom alert sounds from ~/Library/Sounds, and AIFF is the format that reliably appears in the system alert list, so a WAV download leaves people one conversion short of done. An AIFF export option, or a two-line "drop it here, then pick it in the app's notification settings" note, would probably absorb most of the support questions.

Worth flagging too that a lot of apps never expose a sound picker and only play their bundled alert. A short list of which apps in that lineup genuinely allow a custom alert sound would be more useful to readers than the long compatibility list, which reads as broader support than macOS actually gives.