Capital.com vs IG API
The same fields from the Capital.com record and the IG record, side by side. No winner is picked: which one suits you depends on what you are building.
Independent and unofficialNewest check
Risk warning: CFDs and spread bets are complex instruments and come with a high risk of losing money rapidly due to leverage. You can lose money on these products, and each provider publishes its own loss figure under FCA rules. You should consider whether you understand how they work and whether you can afford to take the high risk of losing your money. Automated and API trading can amplify losses through bugs, connectivity failures and runaway orders.
What the two records show
Differences you can see in the records themselves. These are counts of what this site holds, not a verdict on either API.
- Capital.com is recorded as a broker with an API of its own. IG is recorded as a broker with an API of its own.
- This site documents 36 endpoints for Capital.com and 49 endpoints for IG. That counts what has been documented here, not what each API offers.
- This site has decoded 24 error codes for Capital.com and 132 error codes for IG.
- The limits register holds 1 limit record for Capital.com and 5 limit records for IG. Each limit record carries its own scope.
- The Capital.com record holds a demo claim, verified at its source. The IG record holds a demo claim, verified at its source. The wording of each is in the Demo row below.
- Claims marked unverified or as sources conflicting: 0 in the Capital.com record and 1 in the IG record. Each is labelled where it appears.
- A quickstart is built here for both.
Capital.com and IG, field by field
| Field | Capital.com | IG |
|---|---|---|
| Kind | Broker with its own API | Broker with its own API |
| API family | REST, WebSocket | REST, Streaming |
| How you get access | Enable 2FA, then Settings > API integrations > Generate new key, with a custom key password.Capital.com Public APIchecked | API keys are only issued to existing live account holders: generate one in My IG > Settings > API keys.How to use IG APIchecked |
| Who can use it | Any Capital.com account (demo or live) with 2FA enabled. Regional limits not published.Capital.com Public APIchecked | Spread bet and CFD accounts only. Share dealing, ISA and SIPP are not supported (error stockbroking-not-supported).trading-ig FAQ (community source)checked |
| Demo | Yes: separate demo base URL.Capital.com Public APIchecked | Partial: demo API works, but no key from a standalone demo account unless it is linked to a live account.How to use IG APIchecked |
| Authentication | POST /session with the X-CAP-API-KEY header plus login credentials returns CST and X-SECURITY-TOKEN, sent on later calls. The session expires after 10 minutes of inactivity.Capital.com Public APIchecked | API key plus username and password returns CST and X-SECURITY-TOKEN, valid 12 hours on a rolling basis with each call resetting the clock on the IG Labs FAQ, while IG's REST trading API guide says 6 hours at first, extended up to a maximum of 72 hours: a disagreement between two IG pages that the blocked reference page could not settle on 23 Sep 2026. The v3 OAuth access token lasts as long as the login response says, with a refresh token that expires later. All tokens are invalidated during weekend maintenance.Sources conflict IG Labs FAQ: 12 hours between calls, reset by each call. IG Labs REST trading API guide: 6 hours at first, extended up to 72 hours while in use.IG Labs REST trading API guidechecked |
| Streaming | WebSocket wss://api-streaming-capital.backend-capital.com/connect, maximum of 40 epics per subscription; the session lasts 10 minutes and is kept alive with ping.Capital.com Public APIchecked | Streaming runs on Lightstreamer: IG's Streaming API Guide starts by sending you to the Lightstreamer client library, and the server address to connect to comes back from the /session call. By default a connection holds up to 40 simultaneous subscriptions. The guide asks you to contact IG to raise that quota and the FAQ says to manage it by unsubscribing and subscribing as needed; both warn that opening extra connections to get past it may cost you the API key or your API permissions. The streaming API does not take OAuth tokens, only the CST and X-SECURITY-TOKEN pair.IG Labs Streaming API Guidechecked |
| History depth | Candles: max 1,000 per request (default 10), MINUTE to WEEK. Activity history: max 1 day per from/to call. Transactions default to last 10 minutes.Capital.com API referencechecked | Up to 20 years of price history depending on resolution; 10,000 historical data points per week. Transactions and activity history are paged.IG: How to use IG APIchecked |
| Limits |
|
|
| Endpoints documented here | 36 | 49 |
| Error codes decoded here | 24 | 132 |
| Official documentation | open-api.capital.com | labs.ig.com |
Go deeper on each side
Capital.com
- Capital.com API page, the full record
- Capital.com API quickstart, credentials to a first call
- Capital.com API limits, in the table above
- Capital.com API error codes, each with its fix
- Capital.com API endpoints, each with its source
- Get your Capital.com trade history into a spreadsheet
- Capital.com API with Python
IG
- IG API page, the full record
- IG API quickstart, credentials to a first call
- IG API limits, in the table above
- IG API error codes, each with its fix
- IG API endpoints, each with its source
- ChatGPT trading bot with the IG API, the safe way
- Get your IG trade history into a spreadsheet
- IG deal confirms: turning a deal reference into a result
- IG demo API key: how to get one and what it allows
- IG streaming with Python
All comparisons. New to this? Getting started with API trading.