---
title: "Checks EIRP (Effective Isotropic Radiated Power) compliance against regional regulatory limits for LoRa and Meshtastic operation. Computes EIRP from transmit power, antenna gain, and cable loss, then compares against FCC (US, 36 dBm), ETSI (EU, 16.15 dBm), ACMA (Australia, 30 dBm), IC (Canada, 36 dBm), and ARIB (Japan, 13 dBm) limits. Returns compliance status, margin in dB, and a warning message if over the limit. Critical for Meshtastic deployments using aftermarket high-gain antennas which can easily exceed ETSI/JP limits. Accepts tx_power and antenna_gain from meshtastic_range for chain validation."
method: POST
path: "/api/eirp_compliance"
tags: ["mesh"]
---

# Checks EIRP (Effective Isotropic Radiated Power) compliance against regional regulatory limits for LoRa and Meshtastic operation. Computes EIRP from transmit power, antenna gain, and cable loss, then compares against FCC (US, 36 dBm), ETSI (EU, 16.15 dBm), ACMA (Australia, 30 dBm), IC (Canada, 36 dBm), and ARIB (Japan, 13 dBm) limits. Returns compliance status, margin in dB, and a warning message if over the limit. Critical for Meshtastic deployments using aftermarket high-gain antennas which can easily exceed ETSI/JP limits. Accepts tx_power and antenna_gain from meshtastic_range for chain validation.

`POST /api/eirp_compliance`

## Request

- Base URL: `https://calc.engineer`
- URL: `https://calc.engineer/api/eirp_compliance`
- Auth: none declared

## Request body

- object
  - `tx_power_dbm` number, required: Conducted transmit power at the radio output in dBm. Typical LoRa: 14-22 dBm.
  - `antenna_gain_dbi` number, required: Antenna gain in dBi. Stock Meshtastic antennas: 2-3 dBi. External: 6-10+ dBi.
  - `cable_loss_db` number: Coaxial cable and connector loss in dB. Set 0 for devices with integrated antennas.
  - `region` 'FCC_US' | 'ETSI_EU' | 'ACMA_AU' | 'IC_CA' | 'JP' | 'custom': Regulatory region for EIRP limit lookup. FCC_US: 36 dBm, ETSI_EU: ~16 dBm, ACMA_AU: 30 dBm, IC_CA: 36 dBm, JP: 13 dBm.
  - `custom_limit_dbm` number: Custom EIRP limit in dBm. Only used when region is 'custom'.

## Response `200`

Computed result for eirp_compliance

- object
  - `result` object, required
    - `eirp_dbm` number, required: Calculated EIRP in dBm: tx_power + antenna_gain - cable_loss.
    - `eirp_watts` number, required: Calculated EIRP converted to watts.
    - `limit_dbm` number, required: Regional EIRP limit in dBm.
    - `limit_watts` number, required: Regional EIRP limit converted to watts.
    - `margin_db` number, required: Margin below the limit in dB. Positive = compliant, negative = over limit.
    - `compliant` boolean, required: True if EIRP is at or below the regional limit.
    - `region_name` string, required: Human-readable region name.
    - `warning` string, required: Warning message if non-compliant, or empty string if compliant.
  - `tool` string, required
  - `version` string, required
  - `computed_at` string, date-time, required
  - `chain` object, required
    - `feeds` unknown[]
      - unknown
    - `accepts_from` unknown[]
      - unknown

## Other responses

- `400`: Validation error or invalid JSON
- `404`: Tool not found

---

[API](https://skmtc.dev/calc/apis/calc-engineer-api.md) · [All operations](https://skmtc.dev/calc/apis/calc-engineer-api/llms.txt) · [OpenAPI document](https://skmtc.dev/calc/apis/calc-engineer-api/revisions/8830480ec488?raw)