Production Test Calculator
Calculate GOR, GLR, WOR, water cut, and BOE/d from separator test data. Includes shrinkage correction and API fluid classification.
Separator Test Data
Test Results
GOR
--
scf/bbl
GLR
--
scf/bbl
Water Cut
--
%
BOE/d
--
barrels oil equivalent
WOR
--
Total Liquid
--
bbl/d
Oil SG
--
Choke (in)
--
Fluid Classification (from GOR)
--
| Fluid Type | GOR Range (scf/bbl) | API Gravity | Bo (RB/STB) |
|---|---|---|---|
| Black Oil | < 2,000 | < 40 | < 2.0 |
| Volatile Oil | 2,000 - 3,300 | 40 - 50 | > 2.0 |
| Retrograde Condensate | 3,300 - 50,000 | 40 - 60 | -- |
| Wet Gas | 50,000 - 100,000 | > 60 | -- |
| Dry Gas | > 100,000 | -- | -- |
Shrinkage Correction (Separator to Stock Tank)
Estimated formation volume factor (Bo) to correct separator oil to stock-tank conditions.
Est. Bo
--
RB/STB
Shrinkage Factor
--
1/Bo
Stock Tank Oil
--
STB/d
How this was calculated
GOR = Gas Rate (Mcf/d) x 1000 / Oil Rate (bbl/d) [scf/bbl]
GLR = Gas Rate x 1000 / (Oil + Water) [scf/bbl total liquid]
Water Cut = Water / (Oil + Water) x 100 [%]
BOE = Oil (bbl/d) + Gas (Mcf/d) / 6 [6 Mcf = 1 BOE]
Bo (Standing correlation): Bo = 0.972 + 1.47e-4 x [Rs x (gas_sg/oil_sg)^0.5 + 1.25 x T]^1.175
Oil SG = 141.5 / (API + 131.5)
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Production tests are the foundation of reservoir surveillance and well performance evaluation. During a separator test, well fluids are routed through a test separator where oil, gas, and water are measured individually. The resulting rates, combined with wellhead and separator conditions, provide the data needed to calculate key production metrics: GOR, GLR, water cut, and BOE.
The gas-oil ratio (GOR) is one of the most important diagnostic parameters. It indicates the type of reservoir fluid and how the reservoir is performing. Increasing GOR over time may indicate gas cap expansion or solution gas drive depletion, while decreasing GOR can signal pressure maintenance or water encroachment. The fluid classification from GOR helps engineers select appropriate correlations for reservoir and production engineering calculations.
All calculations run entirely in your browser. Built by Groundwork Analytics.