Create Weight Log
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Create Weight Log

Creates a weight log entry

Scope: weight


POST /1/user/[user-id]/body/log/weight.json

URI Arguments
user-id required The encoded ID of the user. Use "-" (dash) for current logged-in user.

Query Parameters
weight required Weight measurement in the format X.XX. decimal
date required The date the weight measurement was recorded in the format yyyy-MM-dd. string ($date)
time optional The timestamp the weight measurement was recorded in the format HH:mm:ss. If a value is not provided, the timestamp will be the last second of the day. string ($time)

Request Headers
authorization required Specify the token type and Fitbit user’s access token.
Token type: Bearer
accept optional The media type of the response content the client is expecting.
Supported: application/json
accept-language optional The measurement unit system to use for response values. See Localization.
accept-locale optional The locale to use for response values. See Localization.
content-length required According to RFC 7230, section 3.3.2, this HTTP request requires the Content-Length header field containing the anticipated size of the payload body.


curl -X POST "" \
-H "accept: application/json" \
-H "authorization: Bearer <access_token>" \
-H "content-length: <message_body_size>"


Element Name Description
weightLog : bmi Calculated BMI in the format X.XX
weightLog : date Log entry date in the format yyyy-MM-dd
weightLog : logId Weight Log IDs are unique to the user, but not globally unique.
weightLog : source The source of the weight log. See "source" values for more information.

Support: API | Aria | AriaAir | Withings
weightLog : time Time of the measurement; hours and minutes in the format HH:mm:ss, set to the last second of the day if not provided.
weightLog : weight Weight in the format X.XX, in the unit system that corresponds to the Accept-Language header provided or if not provided in metric.
  "weightLog": [
      "bmi": 25.91,
      "date": "2019-03-01",
      "logId": 1553067494000,
      "source": "Aria",
      "time": "07:38:14",
      "weight": 200

Response Headers
content-type The media type of the response content being sent to the client.
Supported: application/json
fitbit-rate-limit-limit The quota number of calls.
fitbit-rate-limit-remaining The number of calls remaining before hitting the rate limit.
fitbit-rate-limit-reset The number of seconds until the rate limit resets.

Note: The rate limit headers are approximate and asynchronously updated. This means that there may be a minor delay in the decrementing of remaining requests. This could result in your application receiving an unexpected 429 response if you don't track the total number of requests you make yourself.

Response Type

HTTP Status Code HTTP response code. List of codes are found in the [Troubleshooting Guide](/build/reference/web-api/troubleshooting-guide/error-messages/
Status Message Description of the status code.
Response Body Contains the JSON response to the API call. When errors are returned by the API call, the errorType, fieldName and message text will provide more information to the cause of the failure.

Response Codes
201 A successful request.
400 The request had bad syntax or was inherently impossible to be satisfied.
401 The request requires user authentication.

Note: For a complete list of response codes, please refer to the [Troubleshooting Guide](/build/reference/web-api/troubleshooting-guide/error-messages/

Additional Information

"source" values

This field returns information on whether the user’s body fat or weight data was automatically or manually entered. It includes the following values:

  1. API: The weight and/or body fat data originated from a 3rd party integration using the Web API, the data was manually entered into the Fitbit mobile or web application, or the data recorded by a predefined scale was manually edited.
  2. Aria: The weight and/or body fat data originated from an Aria or Aria 2 scale.
  3. AriaAir: The weight and/or body fat data originated from an Aria Air scale.
  4. Withings: The weight and/or body fat data originated from a Withings scale.