This guide provides a comprehensive overview of the Inventory and Gains API that Taxbit offers, designed to enable clients to effectively display updated inventory and gain/loss data. By leveraging these APIs, clients can enhance the end-user experience, providing comprehensive insights that help end-users manage and understand their digital asset portfolios.


This guide is designed for clients who send digital asset transactions to Taxbit.

Inventory refers to the collection of assets that a user holds, which have not been disposed of. Inventory is organized into “lots”, with each associated with additional metadata such as cost basis and acquisition date. This metadata is used to calculate taxable gains when the assets are sold or otherwise disposed of. Inventory information can answer common questions such as, “How much of an asset do I own?” and “What are my unrealized gains for a particular asset?”. For more information about inventory, including information on disposition methods, please refer to

In order to leverage near real-time inventory, transactions must be sent to TaxBit in sequential order as soon as reasonably possible after the transaction is processed.

For more information on SLAs and how to consume live inventory, see SLAs and Asynchronous Behaviors

Gains (and Losses) are the outcomes of disposing assets that represent the taxable implications of a transaction. A realized gain (or loss) represents the amount from a transaction that will be subject to taxation. For more information about the various aspects of Gain / Loss items, please refer to


TaxBit supports two inventory endpoints:

  • /v1/inventory - Provides lot level information for a specified digital asset for a specified account.
  • /v1/inventory/summaries - Provides a summarized view of each digital asset for a specified account.

There are also three gains endpoints:

  • v1/gains/cost-bases - A detailed breakdown of all combined cost bases, proceeds, and gains/losses. These correspond to line items on an IRS form 8949 or form 1099-B.
  • v1/gains/summary - Provides a summarized amount of a user’s realized gains (or losses) for a given time period, usually represented in the fiat used to value the disposed assets (e.g. USD)
  • v1/gains/breakdown - Provides a summarized amount of a users realized gains (or losses) broken down into long- and short-term periods.



Before using any of the following APIs, you must have proper Organization, Payer and Account objects defined within TaxBit’s system. Additionally, your Payer must have a disposition_method (e.g. HIFO, FIFO) configured to manage inventory. Once this is complete, you’re ready to submit transactions and query the resulting inventory and gains.

Please work with your Taxbit Implementation Manager if you have any questions about this process.

Key Terms

Inventory terms and definitions can be found directly on the Inventory API Reference.

Gains terms and definitions can be found directly on the Gains API Reference.