Speechify Text to Speech Javascript API. Everything You Need to Get Started. The best guide to get you started with the Speechify Text to Speech Javascript API.

If you’re looking to integrate Speechify’s Text-to-Speech (TTS) functionality using their JavaScript API, here’s a clear guide to help you get started, including requirements, supported features, account setup, and code samples.

Try a better alternative to the Speechify Text to Speech Javascript API. PlayHT voice quality is the best in the industry and also features one of the lowest latencies. You can get started, right now. No need to wait.

1. Requirements

Before you begin, you’ll need the following:

• Node.js: Speechify’s API works with server-side JavaScript, so make sure you have Node.js installed.
• npm: You’ll need npm (Node Package Manager) to install the SDK.
• API Key: You’ll need an API key from Speechify to authenticate requests. This requires setting up an account with Speechify to generate your API key.

2. What’s Supported

The Speechify API supports generating audio from text in several formats:

• Audio Formats: The API supports mp3, wav, ogg, and aac formats.
• Voice Selection: You can choose from a variety of voices by providing a voiceId parameter during the request.
• Access Token Management: For client-side implementations, Speechify offers a way to manage short-lived access tokens.

3. Setting Up Accounts and Generating Keys

To use the Speechify API, follow these steps:

• Sign up for a developer account on Speechify’s platform.
• Once logged in, navigate to your account dashboard to generate an API key.
• You’ll use this key in all requests to authenticate against Speechify’s servers.

4. Getting Started: Installation and Setup

First, install the Speechify SDK for Node.js:

npm install @speechify/api-sdk

Now, let’s jump into some basic code.

Note: Looking for a much faster Text to Speech Javascript API that’s been put to the test with the most demanding apps? Try the lowest latency text to speech API from PlayHT.

Server-Side Audio Generation

This is the typical use case where you send text to Speechify and get back the corresponding audio.

import { Speechify } from "@speechify/api-sdk";

const speechify = new Speechify({
    apiKey: "YOUR_API_KEY",  // Replace with your actual API key
});

const generateAudio = async () => {
    const response = await speechify.audioGenerate({
        input: "Hello, world!",
        voiceId: "george",  // Replace with the voice ID you prefer
        audioFormat: "mp3", // You can change this to 'wav', 'ogg', or 'aac'
    });
    const audio = response.audioData;

    // Save or stream the audio as needed
    someStorage.saveFile("audio.mp3", audio);
};

generateAudio();

Server-Side Authentication Token Generation

If you plan on allowing users to interact with Speechify’s API from the client side, you’ll need to generate short-lived access tokens on the server.

import { Speechify } from "@speechify/api-sdk";

const speechify = new Speechify({
    apiKey: "YOUR_API_KEY",
});

// Issue access tokens to be used by the client
const generateToken = async (req, res) => {
    const tokenResponse = await speechify.accessTokenIssue("audio:all");
    res.json(tokenResponse);  // Send the token to the client
};

// Example: POST /speechify-token route in your Express.js server
webServer.post("/speechify-token", generateToken);

Client-Side Audio Generation

On the client side, you’ll need to first fetch a token from the server and then generate the audio using Speechify.

import { Speechify } from "@speechify/api-sdk";

const speechify = new Speechify();

const generateAudioClientSide = async () => {
    // Fetch token from the server
    const tokenResponse = await fetch("/speechify-token", { method: "POST" });
    const token = await tokenResponse.json();

    // Set the token on the client
    speechify.setAccessToken(token.accessToken);

    // Generate audio
    const response = await speechify.audioGenerate({
        input: "Hello from the client!",
        voiceId: "george",
        audioFormat: "mp3",
    });

    const audioElement = new Audio();
    audioElement.src = URL.createObjectURL(new Blob([response.audioData], { type: "audio/mpeg" }));
    audioElement.play();  // Play the generated audio
};

generateButton.addEventListener("click", generateAudioClientSide);

With these examples, you should be ready to integrate Speechify’s Text-to-Speech API into your project. Start by getting your API key, choose the appropriate audio format and voice, and handle authentication efficiently with tokens if needed. For more advanced setups, like voice creation or streaming audio, check the official documentation.

When integrating an API like Speechify into your project, as a developer, you’re naturally focused on getting the basics running first—sending text to the API and receiving speech audio in return. However, there are several things you might find essential for real-world implementation that aren’t explicitly covered in Speechify’s documentation. Let’s break down some of these missing elements.

1. Error Handling and Troubleshooting

When building production-grade applications, it’s crucial to know how to handle errors that arise from network issues, API limits, or incorrect input. Unfortunately, Speechify’s documentation doesn’t provide any real guidance here. Developers typically expect:

• Error codes: What does a 400 vs. 403 mean in the context of this API? Understanding these codes helps in debugging and providing better user feedback.
• Retry logic: What happens when a request times out? Should you retry, or is there a rate limit that would penalize repeated attempts?
• Invalid input management: How do you handle cases where the text is too long or contains unsupported characters?

Without these details, you’re left guessing how to handle failures, which is something you’d need to proactively test and design around.

2. Rate Limits

APIs often come with usage limits, especially those offering services like text-to-speech conversion. However, the Speechify documentation doesn’t discuss any rate limits or throttling that might be in place. Knowing these limits is vital for:

• Planning request volumes: If you’re sending multiple requests for speech generation, you need to ensure you don’t exceed your quota.
• Implementing backoff strategies: What happens if you hit the limit? You’ll need to know if and when to pause requests to avoid disruption.

Understanding these factors early can help avoid surprises as you scale your app or service.

3. Pricing Model and Quotas

A critical part of developing any application that integrates a third-party API is understanding how the usage will affect your budget. Speechify does not provide information on how requests are charged:

• Is it pay-per-request, pay-per-character, or do they offer subscription-based pricing?
• Are there free-tier limits, and if so, what are the restrictions?

This could directly influence how you architect your app. For example, if it’s per character, you might want to batch smaller text inputs together before sending a request.

4. Voice Customization

The API lets you choose predefined voices, but in a real-world app, developers often want the ability to customize voices to match the tone, speed, or even emotional expression required by their use case. Unfortunately, Speechify’s documentation doesn’t discuss options for:

• Custom voices: Can you create unique voices, or are you limited to the ones provided?
• Adjusting voice parameters: While you can pick different voices, is there control over parameters like speed, pitch, or intonation?

Being able to tweak the voice output would be highly beneficial for more personalized or branded audio content.

5. Streaming Audio in Real-Time

Speechify mentions the ability to stream audio but offers little in the way of explaining performance considerations or best practices. Developers would benefit from:

• Guidance on latency: If you’re streaming text-to-speech for real-time applications like live broadcasts or voice assistants, understanding the latency between submitting text and receiving audio is essential.
• Handling interruptions: What happens if the stream is interrupted, or if there’s a network dropout mid-stream?

Without this information, real-time applications might run into performance bottlenecks, leaving developers to figure out the complexities on their own.

6. Advanced Client-Side Integrations

The documentation provides some client-side examples, but they are relatively basic. Many developers today work with front-end frameworks like React, Vue, or Angular, and would benefit from:

• Detailed integration examples: How do you incorporate Speechify into a React component? What’s the best way to handle access tokens and manage them in a single-page application (SPA)?
• Cross-origin requests (CORS): Are there any specific CORS configurations required when making requests from the browser? Handling this can often be a headache when working with client-side APIs.

7. Localization and Multilingual Support

Speechify doesn’t provide much information on multilingual support or localization features, which could be critical for developers building applications aimed at global audiences. Here’s what’s missing:

• Supported languages: A detailed list of the languages and dialects supported by the API would be useful, along with examples of voice options for each language.
• Automatic language detection: If a text contains multiple languages, does Speechify auto-detect and switch voices, or is the developer responsible for splitting and tagging the text?

Without this information, developers working in multilingual contexts will have to do a lot of testing and manual handling.

8. Detailed Authentication Guidance

While the docs provide a basic overview of token management, there’s no deep dive into secure implementation practices, which are critical in production environments:

• Token expiration: How long are tokens valid, and how should you handle token expiration on the client side without disrupting user experience?
• Best practices for API key security: How should developers securely store and rotate API keys, especially in serverless environments or when deploying to the cloud?

Developers integrating with external services need to follow best practices for authentication, and Speechify could offer more clarity here.

9. Deployment to Serverless Environments

Many modern applications are built using serverless architectures like AWS Lambda, Google Cloud Functions, or Azure Functions. Speechify doesn’t provide any deployment guidance for these environments. You might need to know:

• Cold start performance: How fast can the API respond when your serverless function is invoked from a cold start?
• Managing stateless requests: Best practices for handling audio generation and token management in stateless environments.

Understanding these aspects helps optimize performance and ensure that your integration scales efficiently.

In summary, while Speechify’s documentation covers the basics, these areas are critical for developers aiming to integrate their API into a production environment or at scale. Addressing these shortcomings would make the developer experience smoother and reduce the guesswork when it comes to error handling, pricing, customization, and advanced deployment scenarios.