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Salomon
Salomon

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I Got Tired of Paying $99/mo for Options Data — So I Built My Own API tags: python, api, finance, showdev

#python #api #showdev #developer

I build algorithmic trading bots as a side project. Nothing fancy — just small strategies that trade US equity options automatically.

The problem I kept running into wasn't the strategy logic. It was the data.

Every time I wanted to pull real-time options chains, Greeks, or IV, I had two options:

  • Pay $99+/mo to a data provider
  • Scrape something I probably shouldn't be scraping

Neither felt right for a hobbyist project. So I built Market-Options — a simple REST API for US equity options data at $20/mo.

What It Does

It's a plain REST API. No SDK, no special client library — just HTTP requests and JSON responses.

It covers four endpoints:

  • chain — full options chain for a given underlying
  • contract — data for a single contract
  • contracts — batch lookup across multiple contracts
  • contract-overview — Greeks, IV, expiration details

Coverage is the top 100 US equity underlyings, which accounts for roughly 95% of actual US options volume. If you're building a bot that trades SPY, QQQ, AAPL, TSLA, or anything in that tier — it's covered.

Why Only 100 Underlyings?

Because that's what most people actually trade.

When I looked at my own bots, and at what most retail algo traders focus on, the top 100 covers everything practical. Exotic underlyings with low volume are also harder to get real data on reliably — so rather than promise coverage I can't deliver, I focused on doing the core well.

A Simple Example 

curl "https://api.market-option.com/chain?symbol=SPY&expiration=2025-01-17" \
  -H "Authorization: Bearer YOUR_API_KEY"
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Response is clean JSON:

{
  "symbol": "SPY",
  "expiration": "2025-01-17",
  "options": [
    {
      "strike": 480,
      "type": "call",
      "bid": 3.45,
      "ask": 3.50,
      "iv": 0.182,
      "delta": 0.42,
      "gamma": 0.031,
      "theta": -0.18,
      "vega": 0.29
    }
  ]
}
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No parsing headaches, no weird date formats.

Pricing

  • Free tier: 1,000 credits/day — enough to test and build
  • Pro: $20/mo, unlimited within fair use
  • Trial: New accounts get 7 days of Pro, no credit card required

Who It's For

Honestly, it's for people like me — developers who want to build something real with options data without a $99+/mo commitment before they've even proven the strategy works.

If you're building a bot, backtesting a strategy, or just exploring options pricing programmatically, give it a try.

market-option.com

Would love feedback — what endpoints or data points are missing that would make this useful for your use case?

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