IAB Tech Lab

OpenRTB 2.x Protocol

OpenRTB is the real-time bidding protocol between ad exchanges and bidders. IAB Tech Lab publishes the 2.x specification (current release 2.6-202606) with a Protocol Buffers definition (package com.iabtechlab.openrtb.v2, 69 messages) that is maintained in lockstep with the specification and is the standard binary encoding for OpenRTB.

GitHub

Documentation

📖
Documentation
https://github.com/InteractiveAdvertisingBureau/openrtb2.x

Other Resources

🔗
Protobuf
https://raw.githubusercontent.com/api-evangelist/iab-tech-lab/refs/heads/main/grpc/iab-tech-lab-openrtb-v2.proto
🔗
ChangeLog
https://github.com/InteractiveAdvertisingBureau/openrtb2.x/releases
🔗
Protobuf
https://raw.githubusercontent.com/api-evangelist/iab-tech-lab/refs/heads/main/grpc/iab-tech-lab-grpc-index.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: iab-tech-lab:openrtb
name: OpenRTB 2.x Protocol
description: OpenRTB is the real-time bidding protocol between ad exchanges and bidders. IAB Tech Lab
  publishes the 2.x specification (current release 2.6-202606) with a Protocol Buffers definition (package
  com.iabtechlab.openrtb.v2, 69 messages) that is maintained in lockstep with the specification and is
  the standard binary encoding for OpenRTB.
humanURL: https://iabtechlab.com/standards/openrtb/
x-base-url-note: A protocol, not a hosted endpoint — every exchange and bidder pair runs its own OpenRTB
  bid request/response exchange.
tags:
- Real-Time Bidding
- Programmatic
- Protocol Buffers
properties:
- type: Documentation
  url: https://github.com/InteractiveAdvertisingBureau/openrtb2.x
- type: Protobuf
  url: grpc/iab-tech-lab-openrtb-v2.proto
- type: ChangeLog
  url: https://github.com/InteractiveAdvertisingBureau/openrtb2.x/releases
- type: Protobuf
  url: grpc/iab-tech-lab-grpc-index.yml