diff --git a/app/api/v1beta/router.py b/app/api/v1beta/router.py
index 357560b..06999fe 100644
--- a/app/api/v1beta/router.py
+++ b/app/api/v1beta/router.py
@@ -141,3 +141,104 @@ def post_estimations(
 
     except Exception:
         raise HTTPException(status_code=500, detail="Failed to Estimate impacts")
+@api_router_v1beta.post(
+    "/expert-estimations",
+    response_model=dict,
+    tags=["Estimations"],
+    summary="Estimate environmental impacts of an LLM request on unsupported models or custom deployements.",
+    responses=ESTIMATIONS_RESPONSES,
+)
+def post_expert_estimations(
+    output_token_count: int = Body(
+        ...,
+        embed=True,
+        examples=[300],
+        description="Number of tokens generated by the model.",
+    ),
+    model_active_params: float = Body(
+        ...,
+        embed=True,
+        examples=[88],
+        description="Number of active parameters of the model (in billion).",
+    ),
+    model_total_params: float = Body(
+        ...,
+        embed=True,
+        examples=[440],
+        description="Number of total parameters of the model (in billion).",
+    ),
+    request_latency: float | None = Body(
+        default=None,
+        embed=True,
+        examples=[1.56],
+        description="Measured request latency in seconds.",
+    ),
+    tps: float | None = Body(
+        default=None,
+        embed=True,
+        examples=[58],
+        description="Number of tokens generated per second by the model.",
+    ),
+    ttft: float | None = Body(
+        default=None,
+        embed=True,
+        examples=[1.63],
+        description="Time-to-first-token latency in seconds.",
+    ),
+    datacenter_pue: float | None = Body(
+        default=None,
+        embed=True,
+        examples=[1.2],
+        description="Power Usage Effectiveness of the data center.",
+    ),
+    datacenter_wue: float | None = Body(
+        default=None,
+        embed=True,
+        examples=[0.6],
+        description="Water Usage Effectiveness of the data center in L/kWh.",
+    ),
+    electricity_mix_adpe: float = Body(
+        default=1.349e-8,
+        embed=True,
+        examples=[1.349e-8],
+        description="ADPe impact factor of electricity consumption of kgSbeq / kWh (Antimony). (use `GET /v1beta/electricity-mix-zones/{zone}` to get values. Default: world)",
+    ),
+    electricity_mix_pe: float = Body(
+        default=2.5871,
+        embed=True,
+        examples=[2.5871],
+        description="PE impact factor of electricity consumption in MJ / kWh. (use `GET /v1beta/electricity-mix-zones/{zone}` to get values. Default: world)",
+    ),
+    electricity_mix_gwp: float = Body(
+        default=0.45829,
+        embed=True,
+        examples=[0.45829],
+        description="GWP impact factor of electricity consumption in kgCO2eq / kWh. (use `GET /v1beta/electricity-mix-zones/{zone}` to get values. Default: world)",
+    ),
+    electricity_mix_wue: float = Body(
+        default=3.908,
+        embed=True,
+        examples=[3.908],
+        description="WCF impact factor of electricity consumption in L / kWh. (use `GET /v1beta/electricity-mix-zones/{zone}` to get values. Default: world)",
+    )
+):
+    try:
+        impacts = compute_llm_impacts(
+            output_token_count=output_token_count,
+            model_active_parameter_count= model_active_params,
+            model_total_parameter_count = model_total_params,
+            # TODO: remove the high value when the estimations module in EcoLogits (Python) is ready
+            request_latency = request_latency if request_latency is not None else 1e6,
+            tps = tps,
+            ttft = ttft,
+            datacenter_pue = datacenter_pue,
+            datacenter_wue = datacenter_wue,
+            if_electricity_mix_adpe = electricity_mix_adpe,
+            if_electricity_mix_pe = electricity_mix_pe,
+            if_electricity_mix_gwp = electricity_mix_gwp,
+            if_electricity_mix_wue = electricity_mix_wue,
+        )
+        return {"impacts": impacts}
+
+    except Exception:
+        raise HTTPException(status_code=500, detail=f"Failed to Estimate impacts")
diff --git a/tests/v1beta/test_router.py b/tests/v1beta/test_router.py
index a588ea4..9bff28b 100644
--- a/tests/v1beta/test_router.py
+++ b/tests/v1beta/test_router.py
@@ -133,3 +133,50 @@ def test_post_estimations_missing_required_fields():
 
     response = client.post("/v1beta/estimations", json=payload)
     assert response.status_code == 422  # Unprocessable Entity for validation errors
+
+
+
+def test_post_expert_estimations():
+    """Test the POST /expert-estimations endpoint and validate consistency with model results"""
+    payload = {
+        "output_token_count": 300,
+        "model_active_params": 32.3,
+        "model_total_params": 32.3,
+        "tps": 26.8,
+        "ttft": 0.59,
+        "datacenter_pue": 1.09,
+        "datacenter_wue": 0.999,
+        "electricity_mix_adpe": 9.855e-8,
+        "electricity_mix_pe": 9.6884,
+        "electricity_mix_gwp": 0.3844,
+        "electricity_mix_wue": 3.1321
+    }
+
+    # Get the expected impacts directly from llm_impacts
+    expected_impacts = compute_llm_impacts(
+            output_token_count=payload["output_token_count"],
+            model_active_parameter_count= payload["model_active_params"],
+            model_total_parameter_count = payload["model_total_params"],
+            tps = payload["tps"],
+            ttft = payload["ttft"],
+            datacenter_pue = payload["datacenter_pue"],
+            datacenter_wue = payload["datacenter_wue"],
+            if_electricity_mix_adpe = payload["electricity_mix_adpe"],
+            if_electricity_mix_pe = payload["electricity_mix_pe"],
+            if_electricity_mix_gwp = payload["electricity_mix_gwp"],
+            if_electricity_mix_wue = payload["electricity_mix_wue"]
+    )
+
+    # Call the API endpoint
+    response = client.post("/v1beta/expert-estimations", json=payload)
+    assert response.status_code == 200
+
+    response_data = response.json()
+    assert "impacts" in response_data
+    assert response_data["impacts"] is not None
+
+    # Compare the impacts data - convert expected_impacts to dict for comparison
+    expected_impacts_dict = expected_impacts.model_dump()
+    assert response_data["impacts"] == expected_impacts_dict
+
+