Free Resale Pricing API

Quickstart

Single endpoint, single POST. No API key required for the free tier.

curl -X POST https://itemvaluechecker.com/api/check-by-url \
  -H "Content-Type: application/json" \
  -d '{
    "image_url": "https://example.com/your-item.jpg"
  }'

The image URL must be publicly accessible (no auth-walled CDNs). 8MB hard cap on the fetched image. Server fetches + base64-encodes + forwards to the value-check pipeline.

Response shape

{
  "estimated_value": 482,
  "currency": "USD",
  "price_range": { "min": 380, "max": 620 },
  "confidence": 0.74,
  "listing_samples": [
    {
      "title": "Apple MacBook Pro 13\" 2019 Intel i5 8GB 256GB",
      "price": 510,
      "currency": "USD",
      "condition": "Used - Good",
      "url": "https://www.ebay.com/itm/...",
      "image_url": "https://i.ebayimg.com/..."
    },
    /* ...up to 27 listing samples */
  ],
  "cached": false
}

Examples

JavaScript (fetch)

const res = await fetch('https://itemvaluechecker.com/api/check-by-url', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    image_url: 'https://example.com/your-item.jpg',
  }),
});
const data = await res.json();
console.log(data.estimated_value, data.price_range);

Python (requests)

import requests

response = requests.post(
    'https://itemvaluechecker.com/api/check-by-url',
    json={'image_url': 'https://example.com/your-item.jpg'},
    timeout=60,
)
data = response.json()
print(f"${data['estimated_value']} ({data['price_range']['min']}–{data['price_range']['max']})")

Pre-encoded base64 (skip the server-side image fetch)

If your client already has the image bytes (file upload, camera capture), send the base64 directly instead of an image URL. Saves the SSRF-guarded server-side fetch and is faster for browser apps.

POST https://itemvaluechecker.com/api/check-by-url
{
  "image_base64": "data:image/jpeg;base64,/9j/4AAQSkZJ...",
  "max_results": 20
}

Rate limits

429 responses include a Retry-After header in seconds. Daily quota errors include a JSON body with a message field explaining the limit + upgrade path.

Error codes

• 400 invalid_body — request body wasn't valid JSON
• 400 invalid_url — image_url didn't parse as a URL
• 400 unsupported_protocol — only http(s) URLs accepted
• 400 unsafe_host — private/loopback/link-local IPs rejected (SSRF defense)
• 413 image_too_large — fetched image exceeded 8MB
• 415 not_an_image — content-type wasn't image/*
• 429 rate_limited — per-minute burst cap hit (60/min)
• 429 daily_quota_exceeded — free-tier daily cap hit (200/day)
• 502 image_fetch_failed — upstream image host returned non-200
• 502 estimate_failed — value-check pipeline returned an error

Related

• /embed — drop-in iframe widget if you want the full UX, not just the data
• /press — brand assets, boilerplate copy, embed snippet for blogs
• /alternatives — honest comparison against 18 paid + free resale tools