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Fitness Tools

Fat-Free Mass Index

POST
/v1/tools/ffmi

Compute the Fat-Free Mass Index (FFMI) and its height-adjusted form from weight and body fat (or lean mass), and flag whether it exceeds the ~25 natural ceiling.

Request Body required

Section titled “Request Body required ”
object
height
required
object
value
required
number
unit
string
default: cm
Allowed values: cm in mm
weight
required
object
value
required
number
unit
string
default: kg
Allowed values: kg lb
body_fat
number
nullable >= 2 <= 70
lean_mass
object
value
required
number
unit
string
default: kg
Allowed values: kg lb
methods
Any of:
Array<string>
Example
{
  "height": {
    "value": 170,
    "unit": "cm"
  },
  "weight": {
    "value": 80,
    "unit": "kg"
  },
  "body_fat": 12
}

Responses

Section titled “ Responses ”

200

Section titled “200 ”

Fat-Free Mass Index result

object
results
required
Array<object>
object
method
required
string
value
required
number
unit
required
string
detail
object
key
additional properties
consensus
required
object
mean
required
number
median
required
number
min
required
number
max
required
number
n
required
integer

400

Section titled “400 ”

Inputs valid but semantically impossible, or a required method’s inputs are missing.

object
error
required
object
type
required
string
message
required
string
details

422

Section titled “422 ”

Input failed validation (Zod).

object
error
required
object
type
required
string
message
required
string
details