BidRequest.tmax
The maximum time in milliseconds the exchange will wait for bids, network latency included. A value in the request overrides any timeout the exchange published in its integration docs.
Field facts
- Path
tmax- Object
- BidRequest
- Type
- integer
- Requirement
- Optional
- Added
- OpenRTB 2.0
- Spec section
- 3.2.1
How it is used
The bidder's processing budget is tmax minus the round trip to the exchange, so a 200 ms budget with 60 ms of latency leaves about 140 ms. Production values usually sit between 100 and 500 ms. An intermediary that forwards a request should reduce tmax by its own processing time and never raise it. When the field is absent, the timeout agreed during integration applies.
Example
Where the field sits in a payload, with everything else left out:
{
"id": "req-1",
"tmax": 200
}Common mistakes
- Sending 0 or a negative number (
openrtb.request.tmax_non_positive). - Writing seconds, or a whole timeout config, into the field, such as 300000. The validator warns above 10,000 ms.
- Sending the string "120" instead of the integer 120.
Version history
Added in OpenRTB 2.0, and present in the latest snapshot. The table shows how each version's spec text types the field.
| Versions | Type in the spec | Required | Deprecated |
|---|---|---|---|
| 2.0 to 2.2 | integer m 1 t a n e s | No | No |
| 2.3 to 2.6-202606 | integer | No | No |
Related fields
Other BidRequest fields
For a walkthrough of the whole object, read Bid request anatomy.