> For the complete documentation index, see [llms.txt](https://docs.digitalturbine.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.digitalturbine.com/dt-ads-demand/dt-exchange-openrtb-2.5-specs/supported-auction-macros.md).

# Supported Auction Macros

DT allows you to substitute macros based on the [OpenRTB API Specification Version 2.5](https://www.iab.com/wp-content/uploads/2016/03/OpenRTB-API-Specification-Version-2-5-FINAL.pdf) in the `nurl` or `burl` fields, or within the tracking pixel in the `adm` field for auctions. The following table describes the supported DT auction macros.

| Macro                   | Description                                                                                                                                                                              |
| ----------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `${AUCTION_PRICE}`      | <p>The settlement price of the auction.<br>This macro is required in any bid response; otherwise, the bid is considered invalid.</p>                                                     |
| `${AUCTION_ID}`         | ID of the bid request: From the [BidRequest.id](/dt-ads-demand/dt-exchange-openrtb-2.5-specs.md#object-bidrequest) attribute.                                                            |
| `${AUCTION_BID_ID}`     | ID of the bid: From the [BidRequest.id](/dt-ads-demand/dt-exchange-openrtb-2.5-specs.md#object-bidrequest) attribute.                                                                    |
| `${AUCTION_IMP_ID}`     | ID of the impression won: From the [imp.id](/dt-ads-demand/dt-exchange-openrtb-2.5-specs.md#object-imp) attribute.                                                                       |
| `${AUCTION_SEAT_ID}`    | ID of the bidder seat for whom the bid is made.                                                                                                                                          |
| `${AUCTION_AD_ID}`      | ID of the ad markup the bidder wishes to serve: From the [`bid.adid`](/dt-ads-demand/dt-exchange-openrtb-2.5-specs.md) attribute.                                                        |
| `${AUCTION_CURRENCY}`   | The currency used in the bid. Digital Turbine only supports USD.                                                                                                                         |
| `${AUCTION_MIN_TO_WIN}` | <p>The minimum bid the bidder needs to win the auction.<br>Supported in the <a href="/dt-ads-demand/dt-exchange-openrtb-2.5-specs.md#object-seatbid">seatbid.bid.nurl</a> attribute.</p> |
| `${AUCTION_LOSS}`       | Auction loss reason code.                                                                                                                                                                |


---

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