Why I Chose Local TTS Over Cloud APIs

Jul 24, 2025#AI#ML#TTS

When I first started building TinyTTS, a macOS app for turning text into high-quality speech, one of the biggest decisions I had to make was where the speech synthesis would happen. The popular route is using a cloud-based API like OpenAI’s, Google Cloud Text-to-Speech, or ElevenLabs. These services offer powerful, realistic voices that are just an HTTP request away.

But I didn’t go that route.

Instead, I built TinyTTS to run models locally on your Mac, giving users a completely offline, private, and fast text-to-speech experience. In this post, I want to share why I chose local TTS over cloud APIs, and why I think more apps — especially creative tools — should go local too.

Privacy Should Be a Default, Not a Premium

If you’re a content creator, writer, or someone working with sensitive material, sending your scripts, notes, or inner thoughts to a third-party server isn’t always ideal.

With local TTS, your text never leaves your device. There’s no uploading to the cloud, no external logs, no privacy disclaimers buried in a terms-of-service page. Your data stays yours.

TinyTTS runs the TTS model right on your Mac. That means:

  • You can work offline.
  • You don’t need an API key or login.
  • Your data isn’t stored, tracked, or sold.

In an era where online privacy is constantly under threat, this was a no-brainer for me.

Instant Response, No API Limits

Cloud-based APIs are fast — until they’re not.

You’re often at the mercy of server latency, rate limits, and unpredictable downtimes. You might be halfway through a YouTube script and suddenly hit a rate cap or lose your internet connection. That breaks the creative flow.

Local TTS doesn’t depend on any external service. Once the model is loaded, TinyTTS responds instantly. You can:

  • Synthesize as much as you want, without worrying about usage caps.
  • Run multiple jobs in batch.
  • Pause, resume, and experiment — all without lag.

It’s like having a personal AI voice engine running in your studio.

No Recurring Costs or Token Burn

Many cloud TTS APIs operate on a per-character pricing model. That’s fine for small tasks, but if you’re generating large scripts, podcast voiceovers, or audiobook content, the costs add up quickly.

Some examples:

  • OpenAI charges per character for TTS synthesis.
  • ElevenLabs has monthly limits based on voice generation minutes.
  • Google Cloud and Amazon Polly charge by text length and usage.

With TinyTTS, once you download a model, you can use it forever. No tokens. No bills. No stress. For indie creators and small teams, that cost control is empowering.

The Quality Is Getting Shockingly Good

A few years ago, local TTS models lagged behind — they were robotic, slow, and hard to set up.

Not anymore.

Thanks to open-source efforts like Kokoro TTS, Bark, and Coqui, you can now run natural-sounding AI voices on consumer hardware. These models are:

  • Compact (some are just a few hundred MB)
  • Fast enough for near real-time synthesis
  • Tunable and offline-compatible

TinyTTS uses Kokoro TTS under the hood, a modern model that supports expressive speech, multilingual synthesis, and great voice character. In many cases, users are surprised it’s not cloud-based at all.

Of course, cloud voices still lead in ultra-realism, but local models are closing the gap — fast.