ToolAssay

Fractional excretion of sodium (FENa) from plasma and urine sodium and creatinin

Fractional excretion of sodium (FENa) from plasma and urine sodium and creatinine. Espinel 1976 oliguric ARF strata. Deterministic published formula with citation; not a diagnosis.

Asked 1.4x its listed price for its own exampleour last check, 2026-09-28
1 of 1checks answered this week
257 msmedian answer time
$0.005listed price per call
$0.007price it asked us

Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.

Endpoint

POST https://api.magentlab.com/api/calc/fena

CategoryEverything else
Provider hostapi.magentlab.com
Networkseip155:8453
Payment schemesexact
Self-reported calls, 30 days0 from 0 payers (the provider's figure, not ours)

Our checks, last 30 days

DayResultHTTPAskedTime
2026-09-28 valid payment request 402$0.007 257 ms

Example input (from the provider)

{
  "body": {
    "items": [
      {
        "creatinine_mg_dl": 2,
        "creatinine_umol_l": 176.84,
        "sodium_mmol_l": 140,
        "urine_creatinine_mg_dl": 100,
        "urine_creatinine_umol_l": 8842,
        "urine_sodium_mmol_l": 20
      },
      {
        "creatinine_mg_dl": 2,
        "creatinine_umol_l": 176.84,
        "sodium_mmol_l": 140,
        "urine_creatinine_mg_dl": 100,
        "urine_creatinine_umol_l": 8842,
        "urine_sodium_mmol_l": 20
      }
    ]
  },
  "method": "POST",
  "type": "http"
}

Promised output schema (from the provider)

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "input": {
      "additionalProperties": false,
      "properties": {
        "body": {
          "additionalProperties": false,
          "properties": {
            "items": {
              "items": {
                "properties": {
                  "creatinine_mg_dl": {
                    "description": "Plasma creatinine in mg/dL (0.1-20). Provide this or creatinine_umol_l.",
                    "type": "number"
                  },
                  "creatinine_umol_l": {
                    "description": "Plasma creatinine in \u00b5mol/L (9-1768). Converted as mg/dL = \u00b5mol/L / 88.42.",
                    "type": "number"
                  },
                  "sodium_mmol_l": {
                    "description": "Plasma or serum sodium in mmol/L (110-160).",
                    "type": "number"
                  },
                  "urine_creatinine_mg_dl": {
                    "description": "Urine creatinine in mg/dL (1-500). Provide this or urine_creatinine_umol_l.",
                    "type": "number"
                  },
                  "urine_creatinine_umol_l": {
                    "description": "Urine creatinine in \u00b5mol/L (88-44210). Converted as mg/dL = \u00b5mol/L / 88.42.",
                    "type": "number"
                  },
                  "urine_sodium_mmol_l": {
                    "description": "Urine sodium in mmol/L (1-300).",
                    "type": "number"
                  }
                },
                "required": [
                  "sodium_mmol_l",
                  "urine_sodium_mmol_l"
                ],
                "type": "object"
              },
              "maxItems": 25,
              "minItems": 1,
              "type": "array"
            }
          },
          "required": [
            "items"
          ],
          "type": "object"
        },
        "headers": {
          "additionalProperties": {
            "type": "string"
          },
          "type": "object"
        },
        "method": {
          "const": "POST",
          "type": "string"
        },
        "type": {
          "const": "http",
          "type": "string"
        }
      },
      "required": [
        "type",
        "method"
      ],
      "type": "object"
    },
    "output": {
      "properties": {
        "example": {
          "type": "object"
        },
        "type": {
          "type": "string"
        }
      },
      "required": [
        "type"
      ],
      "type": "object"
    }
  },
  "required": [
    "input"
  ],
  "type": "object"
}

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