Groq API Error Codes Explained: 400, 401, 429, 5xx and Fixes

Groq speaks the OpenAI error envelope, which is convenient right up to the moment it isn't: the same error.type strings carry Groq-specific meanings, and Groq ships a couple of status codes the OpenAI SDK has never heard of.

The single most expensive mistake in Groq integrations is treating every non-200 the same way: one generic catch block, one blind retry loop. Half of Groq's error codes are deterministic — retrying them cannot succeed, it only burns quota and hides the real cause. This guide splits them into the ones you fix, the ones you wait out, and the ones you fail over on.

Every Groq API Error Code

Codes below are what Groq returns in production today. Response shapes drift as APIs version, so log the full body — the message text usually names the failing field, and that detail is what turns a 20-minute debug into a 20-second one.

The Groq Error That Wastes the Most Time

Groq's signature failure is a 404 model_not_found on a model that worked last month. Groq retires hosted models faster than any other major inference provider, so a deployment that has not been touched in a quarter can break with nothing wrong on your side and nothing wrong on Groq's. Pin model names in config, not in code, and treat a sudden 404 as a deprecation notice you missed rather than an outage.

Retry or Don't: The Decision Table

This is the part most error handling gets wrong. Retrying a deterministic error is strictly worse than failing fast — it delays the real signal and, on paid tiers, multiplies the bill.

Error Handling That Distinguishes All Three

One handler, three behaviours. The important line is the one that does not retry.

const FATAL = new Set([400, 401, 404, 413, 498, 499]);

async function callGroq(body, attempt = 0) {
  const res = await fetch('https://api.groq.com/openai/v1/chat/completions', {
    method: 'POST',
    headers: { 'Authorization': `Bearer ${process.env.GROQ_API_KEY}`, 'Content-Type': 'application/json' },
    body: JSON.stringify(body),
  });

  if (res.ok) return res.json();

  // Log the body once — it names the failing field on every 4xx
  const detail = await res.text();

  if (FATAL.has(res.status)) {
    throw new Error(`Groq error ${res.status} (not retryable): ${detail}`);
  }

  if (res.status >= 500) {
    // Groq-side: fail over rather than queue behind an outage
    if (attempt >= 1) return callFallbackProvider(body);
  }

  if (attempt >= 4) throw new Error(`Groq failed after retries: ${detail}`);

  const retryAfter = Number(res.headers.get('retry-after')) || 0;
  const backoff = retryAfter * 1000 || (2 ** attempt) * 500 + Math.random() * 500;
  await new Promise((r) => setTimeout(r, backoff));
  return callGroq(body, attempt + 1);
}

Note the fallback triggers on the second 5xx, not the first. A single 500 is often a one-off on a single host; two in a row is an incident, and that is the point where switching providers beats waiting.

Your Error or Theirs? A 60-Second Check

1. Read the status class. 4xx is you, 5xx is Groq. Nothing else in this list matters if you skip this step.
2. Log the response body. Groq names the offending field or model in the message — the status code alone is rarely enough.
3. Try a second API key. If a different key on a different account works, the problem is your account state or quota.
4. Try a different model. A working sibling model rules out an infrastructure-wide incident and points at naming, context length, or per-model capacity.
5. Check groqstatus.com and live Groq monitoring for a confirmed incident before rolling back your own deploy.

For the outage-side playbook, see our Is Groq Down? guide. For quota specifically, the Groq rate limit guide covers headers and tier ceilings in depth.

Where to Send Traffic When Groq Returns 5xx

Fallbacks only help if they are configured before the incident. Each of these runs on independent infrastructure and an independent quota pool, so a Groq 503 does not follow you there.

Frequently Asked Questions

Related Groq Guides

• Is Groq Down? Outage Checking Guide
• Groq API Rate Limits Explained
• Groq API Monitoring Guide
• Groq Status Guide
• API Error Handling: The Complete Guide
• API Rate Limiting: The Complete Guide