Trade Calculator Example

This example shows how to build a simple trade value calculator using the RBLXValue API and vanilla JavaScript.

How It Works

Fetch item values from the API and compare the total value of two sides of a trade.

JavaScript Example

const API_KEY = 'rbx_your_key_here';

async function getItemValue(itemName) {
  const slug = itemName.toLowerCase().replace(/\s+/g, '-');
  const res = await fetch(`https://rblxvalue.com/api/v1/items?slug=${slug}`, {
    headers: { 'X-Api-Key': API_KEY }
  });
  const data = await res.json();
  if (data.error || !data.item) return null;
  const a = data.item.value_source_a || 0;
  const b = data.item.value_source_b || 0;
  return Math.round((a + b) / 2);
}

async function calculateTrade(yourItems, theirItems) {
  const [yourValues, theirValues] = await Promise.all([
    Promise.all(yourItems.map(getItemValue)),
    Promise.all(theirItems.map(getItemValue)),
  ]);

  const yourTotal  = yourValues.reduce((s, v) => s + (v || 0), 0);
  const theirTotal = theirValues.reduce((s, v) => s + (v || 0), 0);
  const difference = theirTotal - yourTotal;

  return {
    yourTotal,
    theirTotal,
    difference,
    fair: Math.abs(difference) / Math.max(yourTotal, 1) < 0.1,
  };
}

// Example usage
const result = await calculateTrade(
  ['seer', 'ginger'],       // your items
  ['chroma-scythe']          // their items
);

console.log(`Your side:   ${result.yourTotal}`);
console.log(`Their side:  ${result.theirTotal}`);
console.log(`Difference:  ${result.difference}`);
console.log(`Fair trade:  ${result.fair}`);

PHP Example

function getItemValue(string $slug, string $apiKey): int {
    $ch = curl_init("https://rblxvalue.com/api/v1/items?slug=" . urlencode($slug));
    curl_setopt_array($ch, [
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_HTTPHEADER     => ["X-Api-Key: $apiKey"],
    ]);
    $data = json_decode(curl_exec($ch), true);
    curl_close($ch);

    if (empty($data["item"])) return 0;
    $a = (int)($data["item"]["value_source_a"] ?? 0);
    $b = (int)($data["item"]["value_source_b"] ?? 0);
    return (int)round(($a + $b) / 2);
}

$yourItems  = ["seer", "ginger"];
$theirItems = ["chroma-scythe"];

$yourTotal  = array_sum(array_map(fn($i) => getItemValue($i, $apiKey), $yourItems));
$theirTotal = array_sum(array_map(fn($i) => getItemValue($i, $apiKey), $theirItems));

echo "Your side: $yourTotal\n";
echo "Their side: $theirTotal\n";

tip

You can use the /api/v1/items?search= parameter to let users search by partial name instead of requiring exact slugs.