Make your first API call
Choose REST or MCP; each path works on its own. Try a Free-plan endpoint in demo mode with ?demo=true and no key, or create a Free API key for 200 calls a day across REST and MCP.
Free covers the most recent quarter and latest data only; full history needs Pro or higher.
curl
Request a live stock profile in demo mode.
curl "https://api.ko.io/api/v1/stocks/AAPL?demo=true"curl -H "Authorization: Bearer ko_live_YOUR_KEY" \
"https://api.ko.io/api/v1/stocks/AAPL"MCP (Claude Code, Codex, Cursor or any MCP client)
Connect the MCP server so your agent can query the data directly. The command below is for Claude Code; configs for Codex, Cursor, Grok and Gemini are on the MCP page.
claude mcp add ko-sec-data --transport http https://mcp.ko.io/mcpclaude mcp add ko-sec-data --transport http https://mcp.ko.io/mcp \
--header "Authorization: Bearer ko_live_YOUR_KEY"Python
Three lines with requests.
import requests
r = requests.get("https://api.ko.io/api/v1/stocks/AAPL", params={"demo": "true"})
print(r.json()["data"])import requests
headers = {"Authorization": "Bearer ko_live_YOUR_KEY"}
r = requests.get("https://api.ko.io/api/v1/holdings/1067983", headers=headers, params={"per_page": 5})
print(r.json()["data"]) # Berkshire Hathaway's latest 13F positionsResponse format
The data requests in this guide return{ data, meta } on success or { error: { code, message } } on failure. data is an array for lists and an object for single resources; the API reference has each endpoint’s data shape.Plans and access
Request limits and data access. Prices shown are billed monthly.
Free
200 calls / day · 500 rows
13F, Form 4, Congress, crypto ETFs, stocks and financials; Fails-to-deliver and Reg SHO threshold lists; N-PORT fund holdings, Form 144, executive pay. Most recent quarter and latest data only.
Pro $60/mo
20,000 calls / day · 5,000 rows
Everything in Free, plus full history; Macro: Treasury, Fed, BLS, CFTC, FDIC, EIA and OFR; 13D / 13G and Form D datasets; PDF portfolio reports (institution 13F); SEC filing document text.
Builder $250/mo
200,000 calls / day · 50,000 rows
Everything in Pro, plus Bulk CSV / JSON export.