IBKR is the platform of choice for the DIY investor who has outgrown a single-country broker. Global market access, multi-currency settlement, low spreads, the works. The trade-off is the construction effort, IBKR gives you the brushes, not the painting.
Arithmos sits in front of IBKR as the construction and execution layer. Describe a global index, the agent picks the local ticker for each listing, runs a backtest in the relevant currency, and on approval places the orders through your IBKR connection.
The flow
- Connect IBKR once via OAuth. Credentials encrypted, you can revoke at any time.
- Describe the index. Example: "European Champions 30, market-cap weighted, capped at 6%."
- Agent picks LSE, Xetra, Euronext and SIX tickers as appropriate.
- Backtest runs against the relevant local benchmark, in local currency.
- Preview the orders, approve, IBKR executes.
Where IBKR genuinely matters
- Multi-currency baskets without home-country bias.
- Access to markets a UK or US broker would not list.
- Lower spreads on large-cap names in liquid local markets.
- Margin and short side, if your index needs it.
- Execution at scale, the API will take the basket cleanly.
Global ex-US large-cap quality compounders, 30 names, market-cap weighted, capped at 6% per name, rebalanced annually in March.
Fees
Arithmos charges the subscription. IBKR charges its standard commissions and FX. There is no markup on either side from us.
FAQ
How does the IBKR connection work?
Arithmos connects to your IBKR account via the official OAuth flow. We never see your password. Credentials are stored AES-256-GCM encrypted, paper and live accounts are separated, and you can revoke the connection at any time from your profile.
Can I run an index that uses LSE, Xetra and NYSE names in one basket?
Yes, that is the case IBKR exists for. The agent picks the right local ticker per listing and the basket executes across exchanges. Currency conversion happens at IBKR's FX, we are not in that price stack.
Will Arithmos place live orders without me looking at them?
Not unless you explicitly enable live execution. The default flow is dry-run preview: the agent shows the orders, you approve, the orders fire. There is a hard legal acknowledgement gate before live execution turns on.
