---
title: "Initialize the simulation"
method: PUT
path: "/initialize/{testid}"
tags: ["Test Setup"]
---

# Initialize the simulation

`PUT /initialize/{testid}`

Initialize simulation to a start time using a warmup period (also resets history and KPI calculations).

## Request body

- object
  - `start_time` number, required — Start time (seconds since Jan 1st, 00:00:00) to initialize the simulation to.
  - `warmup_period` number, required — Warmup period in seconds.

## Response `200`

Simulation initialized successfully.

- SimResponse
  - `message` string — A message describing the response.
  - `payload` object — Current values of all input and measurement signals; always includes "time".
    - `time` number, required — Current simulation time (seconds since Jan 1st, 00:00:00).
  - `status` integer — HTTP status code.

## Changes

- **2026-02-02** `352c81bcd71d` — 2 info
  - api tag `Test Setup` added
  - api tag `Test Setup and Initialization` removed
- **2026-01-02** `e37b5217d73f` — 2 info
  - api tag `Test Setup and Initialization` added
  - api tag `management` removed
- **2025-12-27** `9bb743194905` — 2 info
  - api tag `management` added
  - api tag `Test Setup` removed
- **2025-12-18** `e979b6db7bfd` — 1 info
  - added the required property `payload/time` to the response with the `200` status
- **2025-11-18** `6f370686638c` — 1 info
  - api tag `management` added

[Full history](https://skmtc.dev/ibpsa/apis/boptest-service-api/changes/initialize/:testid/put.md)

---

[API](https://skmtc.dev/ibpsa/apis/boptest-service-api.md) · [All operations](https://skmtc.dev/ibpsa/apis/boptest-service-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/ibpsa/boptest-service-api/revisions/352c81bcd71d/schema)