API Keys

Create and manage your Builder API credentials

Builder API keys authenticate your application with Polymarket’s relayer and enable order attribution. You’ll need these credentials to access gasless transactions and track volume.

Accessing Your Builder Profile

1. Direct Link

   Go to polymarket.com/settings?tab=builder

2. From Menu

   Click your profile image → Select “Builders”

Creating API Keys

In the Builder Keys section of your profile:

1. Click ”+ Create New” to generate a new API key
2. Copy all three values immediately — the secret and passphrase are only shown once
3. Store them securely in your secrets manager or environment variables

Each API key includes three components:

Component	Description	Example
key	Public identifier for your builder account	abc123-def456-...
secret	Secret key for signing requests	base64-encoded-secret
passphrase	Additional authentication value	your-passphrase

The secret and passphrase are only displayed once when created. If you lose them, you’ll need to generate a new key.

Managing Keys

Create separate keys for different environments:

Environment	Purpose
Development	Testing and local development
Staging	Pre-production testing
Production	Live trading

Profile Settings

Your builder profile includes customizable settings:

Setting	Description
Profile Picture	Displayed on the Builder Leaderboard
Builder Name	Public name shown on the leaderboard
Builder Address	Your unique builder identifier (read-only)
Current Tier	Your rate limit tier: Unverified, Verified, or Partner

Environment Variables

Store your credentials as environment variables:

Bash

.env

POLY_BUILDER_API_KEY=your-api-key
POLY_BUILDER_SECRET=your-secret
POLY_BUILDER_PASSPHRASE=your-passphrase

TypeScript

import { BuilderApiKeyCreds } from "@polymarket/builder-signing-sdk";

const builderCreds: BuilderApiKeyCreds = {
  key: process.env.POLY_BUILDER_API_KEY!,
  secret: process.env.POLY_BUILDER_SECRET!,
  passphrase: process.env.POLY_BUILDER_PASSPHRASE!,
};

Python

import os
from py_builder_signing_sdk import BuilderApiKeyCreds

builder_creds = BuilderApiKeyCreds(
    key=os.environ["POLY_BUILDER_API_KEY"],
    secret=os.environ["POLY_BUILDER_SECRET"],
    passphrase=os.environ["POLY_BUILDER_PASSPHRASE"],
)

Rust

use polymarket_client_sdk::auth::Credentials;

let builder_creds = Credentials::new(
    std::env::var("POLY_BUILDER_API_KEY")?.parse()?,
    std::env::var("POLY_BUILDER_SECRET")?,
    std::env::var("POLY_BUILDER_PASSPHRASE")?,
);

Security Best Practices

Practice	Description
Never commit credentials	Use .gitignore to exclude .env files
Use environment variables	Load credentials from env vars, not hardcoded strings
Use a secrets manager	AWS Secrets Manager, HashiCorp Vault, etc. for production
Separate environments	Use different keys for dev, staging, and production
Monitor usage	Check the leaderboard for unexpected volume changes

Never expose Builder API credentials in client-side code. Your secret and passphrase must stay on your server.

Troubleshooting

Rate limit exceeded

Cause: You’ve exceeded your tier’s daily transaction limit.

Solution:

• Wait until the daily limit resets
• Contact Polymarket to upgrade your tier

Lost secret or passphrase

Cause: The secret and passphrase are only shown once when created.

Solution: Create a new API key. You cannot recover the original values.

Next Steps

Attribute Orders

Configure your client to credit trades to your account.

Understand Tiers

Learn about rate limits and how to upgrade.