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Ozor

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7 Free APIs Every Developer Should Bookmark (No Signup Required)

#webdev #tutorial #api #javascript

You know the drill: you need a quick API for IP geolocation, DNS lookup, or crypto prices. You find one, but it wants a credit card, a 3-page signup form, and your firstborn.

Here are 7 APIs you can start using in 30 seconds. One key, 200 free credits, no credit card.

Get Your API Key (30 seconds) 

curl -X POST https://agent-gateway-kappa.vercel.app/api/keys/create
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Response:

{
  "key": "gw_abc123...",
  "credits": 200,
  "expiresAt": "2026-04-03T21:41:12.675Z"
}
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Save that key value. Every API call below costs 1 credit.

1. IP Geolocation

Turn any IP address into a location — country, city, timezone, coordinates. Great for analytics dashboards, geo-targeting, or fraud detection.

curl -H "Authorization: Bearer YOUR_KEY" \
  "https://agent-gateway-kappa.vercel.app/v1/agent-geo/geo/8.8.8.8"
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{
  "ip": "8.8.8.8",
  "found": true,
  "country": "US",
  "timezone": "America/Chicago",
  "latitude": 37.751,
  "longitude": -97.822,
  "eu": false
}
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Bonus endpoints:

  • /geo/me — look up the caller's IP
  • /geo/batch — look up multiple IPs at once (POST)
  • /geo/distance?from=IP1&to=IP2 — distance between two IPs
  • /geo/timezone/IP — just the timezone
  • /geo/country/IP — just the country code

Quick example: geo-target your users 

async function getUserCountry(apiKey) {
  const res = await fetch(
    'https://agent-gateway-kappa.vercel.app/v1/agent-geo/geo/me',
    { headers: { Authorization: `Bearer ${apiKey}` } }
  );
  const data = await res.json();
  return data.country; // "US", "DE", "JP", etc.
}

// Show different pricing based on location
const country = await getUserCountry(API_KEY);
if (['IN', 'BR', 'NG'].includes(country)) {
  showDiscountedPricing();
}
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2. DNS Lookup

Resolve any domain to its IP addresses. Useful for monitoring, security checks, or building network tools.

curl -H "Authorization: Bearer YOUR_KEY" \
  "https://agent-gateway-kappa.vercel.app/v1/agent-dns/api/resolve/github.com"
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{
  "domain": "github.com",
  "ipv4": ["140.82.113.3"],
  "ipv6": [],
  "queryTime": 18,
  "timestamp": "2026-03-04T21:41:21.125Z"
}
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Quick example: domain health checker 

import requests

API_KEY = "YOUR_KEY"
BASE = "https://agent-gateway-kappa.vercel.app"

domains = ["github.com", "google.com", "example.com"]

for domain in domains:
    r = requests.get(
        f"{BASE}/v1/agent-dns/api/resolve/{domain}",
        headers={"Authorization": f"Bearer {API_KEY}"}
    )
    data = r.json()
    ips = data.get("ipv4", [])
    ms = data.get("queryTime", "?")
    print(f"{domain}: {', '.join(ips)} ({ms}ms)")
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Output:

github.com: 140.82.113.3 (18ms)
google.com: 142.250.80.46 (12ms)
example.com: 93.184.215.14 (8ms)
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3. Live Crypto Prices

Real-time prices for 38+ tokens from Binance. BTC, ETH, SOL, XRP, DOGE — updated every few seconds.

curl -H "Authorization: Bearer YOUR_KEY" \
  "https://agent-gateway-kappa.vercel.app/v1/crypto-feeds/api/prices"
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{
  "count": 38,
  "prices": {
    "BTCUSDT": {
      "price": 73189.5,
      "change_pct": 7.69,
      "volume": 16128.63,
      "high": 74050,
      "low": 67400
    },
    "ETHUSDT": {
      "price": 2150.8,
      "change_pct": 9.45
    }
  }
}
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Quick example: price alert bot 

async function checkPrice(apiKey, symbol, threshold) {
  const res = await fetch(
    'https://agent-gateway-kappa.vercel.app/v1/crypto-feeds/api/prices',
    { headers: { Authorization: `Bearer ${apiKey}` } }
  );
  const { prices } = await res.json();
  const token = prices[`${symbol}USDT`];

  if (token && token.price > threshold) {
    console.log(`ALERT: ${symbol} is $${token.price} (above $${threshold})`);
    return true;
  }
  return false;
}

// Alert when BTC crosses $75K
await checkPrice(API_KEY, 'BTC', 75000);
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4. URL Shortener

Shorten any URL programmatically. Returns a clean short link you can share or track.

curl -X POST \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://github.com/trending"}' \
  "https://agent-gateway-kappa.vercel.app/v1/agent-shorturl/api/shorten"
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{
  "slug": "WdzvuC",
  "shortUrl": "https://agent-gateway-kappa.vercel.app/v1/agent-shorturl/WdzvuC",
  "url": "https://github.com/trending",
  "created": "2026-03-04T21:41:24.514Z"
}
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Quick example: bulk URL shortener 

import requests
import json

API_KEY = "YOUR_KEY"
BASE = "https://agent-gateway-kappa.vercel.app"

urls = [
    "https://github.com/trending",
    "https://news.ycombinator.com",
    "https://dev.to"
]

for url in urls:
    r = requests.post(
        f"{BASE}/v1/agent-shorturl/api/shorten",
        headers={
            "Authorization": f"Bearer {API_KEY}",
            "Content-Type": "application/json"
        },
        json={"url": url}
    )
    data = r.json()
    print(f"{url} -> {data['shortUrl']}")
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5. Code Paste Bin

Create shareable code snippets programmatically. Perfect for logging, debugging, or building tools that need to share output.

curl -X POST \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"content":"console.log(\"hello world\")","language":"javascript","expiresIn":"24h"}' \
  "https://agent-gateway-kappa.vercel.app/v1/agent-paste/api/pastes"
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{
  "id": "fsxp2kxs",
  "url": "https://agent-gateway-kappa.vercel.app/v1/agent-paste/api/pastes/fsxp2kxs",
  "rawUrl": "https://agent-gateway-kappa.vercel.app/v1/agent-paste/api/pastes/fsxp2kxs/raw",
  "language": "javascript",
  "lines": 1,
  "bytes": 27
}
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Access the raw content at the rawUrl — useful for automated scripts that need to share output.

6. Crypto Wallet Generator

Generate HD wallets for Ethereum, Bitcoin, Solana, and 6 other chains. The API creates a mnemonic and derives addresses — it never stores keys.

curl -X POST \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"chain":"ethereum"}' \
  "https://agent-gateway-kappa.vercel.app/v1/agent-wallet/wallets/generate"
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{
  "mnemonic": "panel boss toe nurse patient another bunker struggle give word bless victory",
  "addresses": {},
  "warning": "STORE YOUR MNEMONIC SECURELY. This API does not persist keys."
}
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Then derive addresses from the mnemonic:

curl -X POST \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"mnemonic":"panel boss toe nurse...","chain":"ethereum"}' \
  "https://agent-gateway-kappa.vercel.app/v1/agent-wallet/wallets/derive"
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Supports: Ethereum, Bitcoin, Solana, Polygon, Avalanche, BSC, Arbitrum, Optimism, Base.

Security note: Use this for development and testing. For production wallets, generate keys locally.

7. Website Screenshots

Capture screenshots of any URL in multiple viewport sizes.

curl -H "Authorization: Bearer YOUR_KEY" \
  "https://agent-gateway-kappa.vercel.app/v1/agent-screenshot/api/screenshot?url=https://github.com&width=1280&height=720"
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Returns a PNG image. Combine with the URL shortener for shareable screenshot links.

Quick example: site thumbnail generator 

async function captureScreenshot(apiKey, url) {
  const res = await fetch(
    `https://agent-gateway-kappa.vercel.app/v1/agent-screenshot/api/screenshot?url=${encodeURIComponent(url)}&width=1280&height=720`,
    { headers: { Authorization: `Bearer ${apiKey}` } }
  );
  const buffer = await res.arrayBuffer();
  return Buffer.from(buffer);
}
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Bonus: Check Your Credits

Every call costs 1 credit. Check your balance anytime:

curl -H "Authorization: Bearer YOUR_KEY" \
  "https://agent-gateway-kappa.vercel.app/api/keys/balance"
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{
  "credits": 193,
  "usage": "193 credits remaining (~193 API calls)",
  "expires_at": "2026-04-03T21:41:12.675Z"
}
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Need more? Top up with USDC on Base (500 credits per $1).

All 40 Services

These 7 are just the highlights. The full platform has 40 APIs including:

  • Web scraping — extract content from any URL
  • PDF generation — HTML to PDF
  • Image processing — resize, convert, compress
  • Webhook inspector — test and debug webhooks
  • Task scheduling — cron-like job scheduler
  • Secret vault — encrypted key-value storage
  • LLM proxy — unified API for multiple AI models
  • And 25+ more

Browse the full catalog: https://api-catalog-three.vercel.app

Get Started 

# 1. Get your key (free, no signup)
curl -X POST https://agent-gateway-kappa.vercel.app/api/keys/create

# 2. Use any API
curl -H "Authorization: Bearer YOUR_KEY" \
  "https://agent-gateway-kappa.vercel.app/v1/agent-geo/geo/8.8.8.8"
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200 free credits. No credit card. No signup form. Just an API key and curl.

All examples use live endpoints — copy-paste and try them right now.

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