deepgram-rate-limits

Deepgram Rate Limits

Overview

Implement rate limiting, exponential backoff, and circuit breaker patterns for Deepgram API. Deepgram limits by concurrent connections (not requests per second). Understanding this model is key to building reliable integrations.

Deepgram Rate Limit Model

Deepgram uses concurrency-based limits, not traditional requests-per-minute:

Plan	Concurrent Requests (STT)	Concurrent Connections (Live)	Concurrent Requests (TTS)
Pay As You Go	100	100	100
Growth	200	200	200
Enterprise	Custom	Custom	Custom

When you exceed your concurrency limit, Deepgram returns 429 Too Many Requests.

Key insight: You can send unlimited total requests — just not more than your concurrency limit simultaneously.

Instructions

Step 1: Concurrency-Aware Queue

import pLimit from 'p-limit';
import { createClient } from '@deepgram/sdk';

class DeepgramRateLimiter {
  private limit: ReturnType<typeof pLimit>;
  private client: ReturnType<typeof createClient>;
  private stats = { total: 0, active: 0, queued: 0, errors: 0 };

  constructor(apiKey: string, maxConcurrent = 50) {
    // Stay well under plan limit (e.g., 50 of 100 allowed)
    this.limit = pLimit(maxConcurrent);
    this.client = createClient(apiKey);
  }

  async transcribe(source: { url: string }, options: Record<string, any>) {
    this.stats.queued++;
    return this.limit(async () => {
      this.stats.queued--;
      this.stats.active++;
      this.stats.total++;
      try {
        const { result, error } = await this.client.listen.prerecorded.transcribeUrl(
          source, options
        );
        if (error) {
          this.stats.errors++;
          throw error;
        }
        return result;
      } catch (err) {
        this.stats.errors++;
        throw err;
      } finally {
        this.stats.active--;
      }
    });
  }

  getStats() { return { ...this.stats }; }
}

// Usage:
const limiter = new DeepgramRateLimiter(process.env.DEEPGRAM_API_KEY!, 50);
const urls = ['audio1.wav', 'audio2.wav', /* ...hundreds more */];
const results = await Promise.allSettled(
  urls.map(url => limiter.transcribe({ url }, { model: 'nova-3', smart_format: true }))
);

Step 2: Exponential Backoff with Jitter

class RetryableDeepgramClient {
  private client: ReturnType<typeof createClient>;

  constructor(apiKey: string) {
    this.client = createClient(apiKey);
  }

  async transcribeWithRetry(
    source: any,
    options: any,
    config = { maxRetries: 5, baseDelay: 1000, maxDelay: 60000 }
  ) {
    let lastError: Error | null = null;

    for (let attempt = 0; attempt <= config.maxRetries; attempt++) {
      try {
        const { result, error } = await this.client.listen.prerecorded.transcribeUrl(
          source, options
        );
        if (!error) return result;

        // Non-retryable errors (4xx except 429, 408)
        const status = (error as any).status;
        if (status >= 400 && status < 500 && status !== 429 && status !== 408) {
          throw new Error(`Non-retryable error ${status}: ${error.message}`);
        }
        lastError = error;
      } catch (err: any) {
        if (err.message.startsWith('Non-retryable')) throw err;
        lastError = err;
      }

      if (attempt < config.maxRetries) {
        // Exponential backoff: 1s, 2s, 4s, 8s, 16s + random jitter
        const delay = Math.min(
          config.baseDelay * Math.pow(2, attempt) + Math.random() * 1000,
          config.maxDelay
        );
        console.log(`Retry ${attempt + 1}/${config.maxRetries} in ${Math.round(delay)}ms`);
        await new Promise(r => setTimeout(r, delay));
      }
    }
    throw lastError ?? new Error('Max retries exceeded');
  }
}

Step 3: Circuit Breaker

enum CircuitState { CLOSED, OPEN, HALF_OPEN }

class DeepgramCircuitBreaker {
  private state = CircuitState.CLOSED;
  private failureCount = 0;
  private lastFailureTime = 0;
  private successCount = 0;

  constructor(
    private failureThreshold = 5,
    private resetTimeout = 30000,     // 30 seconds
    private halfOpenMaxRequests = 3,
  ) {}

  async execute<T>(fn: () => Promise<T>): Promise<T> {
    if (this.state === CircuitState.OPEN) {
      if (Date.now() - this.lastFailureTime >= this.resetTimeout) {
        this.state = CircuitState.HALF_OPEN;
        this.successCount = 0;
      } else {
        throw new Error(`Circuit OPEN — retry in ${
          Math.ceil((this.resetTimeout - (Date.now() - this.lastFailureTime)) / 1000)
        }s`);
      }
    }

    try {
      const result = await fn();
      this.onSuccess();
      return result;
    } catch (err) {
      this.onFailure();
      throw err;
    }
  }

  private onSuccess() {
    if (this.state === CircuitState.HALF_OPEN) {
      this.successCount++;
      if (this.successCount >= this.halfOpenMaxRequests) {
        this.state = CircuitState.CLOSED;
        this.failureCount = 0;
      }
    } else {
      this.failureCount = 0;
    }
  }

  private onFailure() {
    this.failureCount++;
    this.lastFailureTime = Date.now();
    if (this.failureCount >= this.failureThreshold) {
      this.state = CircuitState.OPEN;
      console.error(`Circuit OPEN after ${this.failureCount} failures`);
    }
  }

  getState() { return CircuitState[this.state]; }
}

Step 4: Combined Rate Limiter + Circuit Breaker

class ResilientDeepgramClient {
  private limiter: DeepgramRateLimiter;
  private breaker: DeepgramCircuitBreaker;
  private retryClient: RetryableDeepgramClient;

  constructor(apiKey: string, maxConcurrent = 50) {
    this.limiter = new DeepgramRateLimiter(apiKey, maxConcurrent);
    this.breaker = new DeepgramCircuitBreaker();
    this.retryClient = new RetryableDeepgramClient(apiKey);
  }

  async transcribe(audioUrl: string, options: Record<string, any> = {}) {
    return this.breaker.execute(() =>
      this.retryClient.transcribeWithRetry(
        { url: audioUrl },
        { model: 'nova-3', smart_format: true, ...options }
      )
    );
  }
}

// Production usage
const client = new ResilientDeepgramClient(process.env.DEEPGRAM_API_KEY!, 50);
const result = await client.transcribe('https://example.com/audio.wav');

Step 5: Usage Monitoring

// Query Deepgram's usage API to track consumption
async function checkUsage(client: ReturnType<typeof createClient>, projectId: string) {
  const { result } = await client.manage.getUsage(projectId, {
    start: new Date(Date.now() - 86400000).toISOString(), // Last 24 hours
    end: new Date().toISOString(),
  });

  const totalMinutes = (result as any).results?.reduce(
    (sum: number, r: any) => sum + (r.hours * 60 + r.minutes), 0
  ) ?? 0;

  console.log(`Last 24h usage: ${totalMinutes.toFixed(1)} minutes`);
  return totalMinutes;
}

Output

• Concurrency-aware request queue with p-limit
• Exponential backoff with jitter for 429/5xx errors
• Circuit breaker (CLOSED -> OPEN -> HALF_OPEN)
• Combined resilient client pattern
• Usage monitoring via Deepgram API

Error Handling

Issue	Cause	Resolution
429 Too Many Requests	Concurrency limit exceeded	Lower maxConcurrent, implement backoff
Circuit breaker OPEN	5+ consecutive failures	Wait for reset, check status.deepgram.com
Queue growing unbounded	Sustained high load	Increase plan limits or scale horizontally
Usage API returns empty	Wrong project ID	Verify project ID from getProjects()

Resources

• Concurrency Rate Limits
• API Rate Limits
• Backoff Strategies
• Usage API