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Check out the x402 Ad Marketplace (UI)

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x402 Ad Marketplace

Buy advertising space on 100+ crypto content sites using USDC with zero gas fees thanks to x402 gasless payments.

No Gas Fees

Pay only the ad price - zero transaction fees

Instant Booking

One signature and you’re live

100+ Sites

Choose from crypto news, DeFi, NFT sites

AI-Powered Content

Submit articles with AI validation and generation

Real Analytics

See traffic data before you buy

Track Everything

Monitor your ads and article requests in real-time

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Quick Start

  • Display Ads
  • Article Submissions
1

Connect Wallet

Visit x402 Ad Marketplace and connect your wallet on Base network
2

Browse Sites

Explore sites with traffic stats, pick your target audience
3

Choose Format & Time

Select ad format (Banner/Sidebar/Leaderboard) and time slot
4

Upload Ad

Provide image URL and landing page
5

Sign & Pay

One signature with USDC - zero gas fees - instant confirmation
Need USDC on Base? Bridge from Ethereum using Base Bridge

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Ad Formats & Pricing

  • Wide banner
  • Leaderboard
970×250 pixels - Wide banner formatPrice: 1 USDC/hourBest for cost-effective campaigns with good visibility
Duration: 1 hour minimum, 7 days (168 hours) maximum

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Article Submissions

Submit article ideas to crypto content sites. AI validates your topic and generates optimized titles and descriptions.

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How It Works

1

Submit Topic or Tweet

Provide a tweet URL, topic idea, or complete article title
2

AI Validation (Free)

AI scores your content (0-100) and generates suggestions if needed
3

Get Approval

  • Score ≥80: Your input is perfect, accepted as-is
  • Score 70-79: Approved with AI-improved suggestions
  • Score <70: Rejected - try a different topic
4

Submit & Pay

One x402 signature to submit your article request
5

Publication

Site publishes your article and you receive the live URL

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Pricing

Prices vary by site, typically $3-50 USDC per article. Each site sets their own rate based on traffic and audience.
Validation is free! You can validate as many ideas as you want before committing to payment.

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API Reference

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Network & Payment Details

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Network
Base
Chain ID: 8453
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Payment Token
USDC
6 decimals
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Protocol
x402
ERC-20 Permit signatures
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Max Price
$1000
Maximum price per booking

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Purchase Ad Slot (x402 Payment)

POST https://x402.anyspend.com/ads/buy
Programmatically purchase ad slots using x402 gasless payments. This endpoint requires x402 payment authorization. Request Body: 
{
  "productId": "slot_abc123",
  "buyerAddress": "0x742d35Cc6...",
  "startTime": "2025-01-15T14:00:00Z",
  "endTime": "2025-01-15T18:00:00Z",
  "adContent": {
    "imageUrl": "https://...",
    "linkUrl": "https://...",
    "altText": "Alt text",
    "title": "Ad title",
    "description": "Description"
  }
}
Parameters:
  • productId (required) - The ad slot ID from /ads/slots
  • buyerAddress (required) - Your wallet address
  • startTime (required) - Start time in ISO 8601 format
  • endTime (required) - End time in ISO 8601 format
  • adContent.imageUrl (required) - Direct URL to ad image
  • adContent.linkUrl (required) - Landing page URL
  • adContent.altText (required) - Image alt text
  • adContent.title (optional) - Ad title
  • adContent.description (optional) - Ad description
JavaScript/TypeScript Example: 
import { wrapFetchWithPayment } from '@b3dotfun/anyspend-x402-fetch';
import { createWalletClient, custom, publicActions } from 'viem';
import { base } from 'viem/chains';

// Create wallet client
const walletClient = createWalletClient({
  account: '0x742d35Cc6...',
  chain: base,
  transport: custom(window.ethereum),
}).extend(publicActions);

// Wrap fetch with x402 payment
const fetchWithPayment = wrapFetchWithPayment(
  fetch,
  walletClient,
  BigInt(1000 * 10 ** 6) // Max 1000 USDC
);

// Purchase ad slot
const response = await fetchWithPayment(
  'https://x402.anyspend.com/ads/buy',
  {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      productId: 'slot_abc123',
      buyerAddress: '0x742d35Cc6...',
      startTime: '2025-01-15T14:00:00Z',
      endTime: '2025-01-15T18:00:00Z',
      adContent: {
        imageUrl: 'https://example.com/ad.jpg',
        linkUrl: 'https://example.com',
        altText: 'My ad',
        title: 'Check out our product!',
        description: 'Limited offer'
      }
    })
  }
);

const result = await response.json();
console.log('Booking ID:', result.data.bookingId);
See x402 SDK documentation for more details on using wrapFetchWithPayment.

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Browse Sites (Free)

GET https://x402.anyspend.com/ads/sites
List all available sites with pagination. This endpoint is free to call. Query parameters:
  • page - Page number (default: 1)
  • limit - Results per page (default: 20, max: 100)
  • search - Search by name/domain/keywords
curl "https://x402.anyspend.com/ads/sites?search=defi&limit=10"

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List All Slots (Free)

GET https://x402.anyspend.com/ads/slots
List all available ad slots across all sites. This endpoint is free to call. 
curl "https://x402.anyspend.com/ads/slots"

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Get Slot Details (Free)

GET https://x402.anyspend.com/ads/slots/:slotId
Returns static slot information including pricing, format, and associated site details. This endpoint is free to call. 
curl "https://x402.anyspend.com/ads/slots/slot_banner_abc123"

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Check Current Ad (Free)

GET https://x402.anyspend.com/ads/slots/:slotId/current-ad
Returns the ad currently running in this slot, or indicates if the slot is available. This endpoint is free to call. 
curl "https://x402.anyspend.com/ads/slots/slot_banner_abc123/current-ad"

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View Your Campaigns (Free)

GET https://x402.anyspend.com/ads/bookings/buyer/:address
Track all your ad bookings - active, pending, and completed. This endpoint is free to call. 
curl "https://x402.anyspend.com/ads/bookings/buyer/0xYourAddress"
Status values:
  • active - Currently running
  • pending - Scheduled for future
  • completed - Campaign ended
Prices in API responses are in USDC wei (6 decimals). Divide by 1,000,000 to get USDC amount.

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Article Submission Endpoints

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Validate Article Idea (Free)

POST https://x402.anyspend.com/articles/validate
Validate an article idea and get AI-generated title and description. This endpoint is free to call - no payment required. Request Body: 
{
  "siteDomain": "baseradar.com",
  "userInput": "How to Use Base Pay for Creators in Your DApp"
}
Parameters:
  • siteDomain (required) - Target site domain (e.g., “baseradar.com”, “solanaecho.com”)
  • userInput (required) - Can be:
    • Complete article title (10-200 characters)
    • Tweet URL (e.g., “https://x.com/username/status/…”)
    • Topic or idea (e.g., “base pay for creators”)
AI Scoring:
  • Score ≥80: Your input is perfect! Used as-is
  • Score 70-79: Good content, AI provides improved suggestions
  • Score <70: Rejected - topic doesn’t fit the site
JavaScript Example: 
const response = await fetch('https://x402.anyspend.com/articles/validate', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    siteDomain: 'baseradar.com',
    userInput: 'How to bridge assets to Base chain'
  })
});

const result = await response.json();
console.log('Approved:', result.data.approved);
console.log('Score:', result.data.score);
console.log('Title:', result.data.suggestedTitle);

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Submit Article Request (x402 Payment)

POST https://x402.anyspend.com/articles/buy
Submit an article request with x402 gasless payment. Requires prior validation approval. Request Body: 
{
  "buyerAddress": "0x742d35Cc6...",
  "siteDomain": "baseradar.com",
  "title": "How to Use Base Pay for Creators in Your DApp",
  "description": "Learn how to integrate Base Pay into your decentralized application..."
}
Parameters:
  • buyerAddress (required) - Your wallet address
  • siteDomain (required) - Target site domain
  • title (required) - Article title (10-200 characters)
  • description (required) - Article description/summary
JavaScript/TypeScript Example: 
import { wrapFetchWithPayment } from '@b3dotfun/anyspend-x402-fetch';
import { createWalletClient, custom, publicActions } from 'viem';
import { base } from 'viem/chains';

// Create wallet client
const walletClient = createWalletClient({
  account: '0x742d35Cc6...',
  chain: base,
  transport: custom(window.ethereum),
}).extend(publicActions);

// Wrap fetch with x402 payment
const fetchWithPayment = wrapFetchWithPayment(
  fetch,
  walletClient,
  BigInt(1000 * 10 ** 6) // Max 1000 USDC
);

// Submit article request
const response = await fetchWithPayment(
  'https://x402.anyspend.com/articles/buy',
  {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      buyerAddress: '0x742d35Cc6...',
      siteDomain: 'baseradar.com',
      title: 'How to Use Base Pay for Creators in Your DApp',
      description: 'Learn how to integrate Base Pay into your decentralized application for seamless creator payments.'
    })
  }
);

const result = await response.json();
console.log('Request ID:', result.data.requestId);

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View Your Article Requests (Free)

GET https://x402.anyspend.com/articles/requests/buyer/:address
Track all your article requests - pending, in progress, and published. This endpoint is free to call. 
curl "https://x402.anyspend.com/articles/requests/buyer/0xYourAddress"
Status values:
  • pending - Waiting for site to write article
  • in_progress - Article is being written
  • published - Article is live (includes publishedUrl)
  • rejected - Article request was declined

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Zero Gas with x402

x402 is the payment protocol that makes crypto payments feel like web2. Traditional crypto payments:
  • ❌ Multiple transactions (approve + transfer)
  • ❌ $5-15 in gas fees
  • ❌ 30-60 second wait times
  • ❌ Complex multi-step flows
With x402:
  • ✅ One signature - no transactions
  • ✅ Zero gas fees
  • ✅ Instant settlement
  • ✅ Simple one-click purchase

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How It Works

  1. You sign a payment authorization message (not a transaction)
  2. x402 facilitator submits the transaction for you
  3. Facilitator pays the gas
  4. You pay only the ad price
Always verify the amount and recipient before signing!

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Security

  • ✅ You control the signature
  • ✅ Signatures expire (can’t be replayed)
  • ✅ One-time use with unique nonce
  • ✅ Amount is locked (can’t charge more)

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Tips for Success

  • Use high contrast colors
  • Keep text large and readable
  • Include a clear call-to-action
  • Test image URL before booking
  • Match sites to your target market
  • Check traffic stats before booking
  • Consider multiple smaller sites vs one large site
Use UTM parameters in your landing page URL:
https://yoursite.com?utm_source=sitename&utm_medium=banner
  • Book 1-2 hours first to test
  • Monitor click-through rates
  • Scale up what works
  • Keep titles between 10-200 characters
  • Be specific and descriptive
  • Match the site’s content focus
  • Use keywords relevant to the site’s audience
  • If you have a great title, submit it directly (10+ chars)
  • Research the site before submitting
  • Check recent articles for tone and topics
  • Tweet URLs work great - AI extracts context
  • Validate multiple ideas before paying
  • Score ≥70 required for approval
  • If score is 70-89, review AI improvements
  • AI optimizes for SEO and engagement
  • Suggested descriptions enhance your submission
  • Use validation to refine your pitch

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Common Issues

You need USDC on Base network. Check that:
  • You’re connected to Base (Chain ID: 8453)
  • You have enough USDC for the total cost
Someone just booked that slot. Refresh and choose a different time.
Currently, bookings cannot be cancelled or refunded. Make sure your ad is ready before booking.
No, ad content is locked at booking time. You’ll need to make a new booking to change it.

Launch Your Campaign

Start advertising on crypto sites in 5 minutes
Related: Article Submission Marketplace • x402 Overview • x402scan →