Water EC (μS/cm & mS/cm) ↔ TDS (ppm 500 NaCl, 640 EU & 700 442 Scale) Converter

Convert Electrical Conductivity (μS/cm & mS/cm) into TDS ppm on the 500, 640, and 700 scales.

TDS on 500 Scale (US / NaCl)
700 ppm
TDS on 700 (442 Hydroponic) Scale 980 ppm
TDS on 640 (European) Scale 896 ppm
Conductivity Factor (CF = 10 × mS/cm) 14 CF
Inputs
⚡ Scenarios:
μS/cm
Electrical Conductivity (EC) at 25°C in microsiemens per centimeter (μS/cm).
Results & Graph
TDS on 500 Scale (US / NaCl)
700 ppm
TDS on 700 (442 Hydroponic) Scale
980 ppm
TDS on 640 (European) Scale
896 ppm
Conductivity Factor (CF = 10 × mS/cm)
14 CF

TDS on 500 Scale (US / NaCl)

Graph 1 • EC (μS/cm) ↔ TDS (ppm) • Domain Architecture & Live Telemetry Maps Electrical Conductivity Micro Siemens through EC (μS/cm) ↔ TDS (ppm) Formula.
FLUID & CHEMICAL CONVERSIO TDS on 500 Scale (US / NaC 700 ppm TDS on 700 (442 Hydroponic 980 ppm EC (μS/cm) ↔ TDS (ppm) • Component Waterfall TDS on 500 Scale (US / NaCl) 700 ppm TDS on 700 (442 Hydroponic) Sc 980 ppm TDS on 640 (European) Scale 896 ppm Conductivity Factor (CF = 10 × 14 CF
Graph 2 • TDS on 500 Scale (US / NaCl) Across Electrical Conductivity Micro Siemens Sweep (40% → 160%) Evaluates TDS_500 = EC_mS × 500; TDS_640 = EC_mS × 640; TDS_700 = EC_mS × 700; across 7 operating points (current input highlighted).
0 ppm 616 ppm 1.2k ppm 280 560μS/cm 420 840μS/cm 560 1.1kμS/cm 700 1.4kμS/cm 840 1.7kμS/cm 980 2.0kμS/cm 1.1k 2.2kμS/cm
Graph 3 • EC (μS/cm) ↔ TDS (ppm) Multi-Scenario Envelope Shows how TDS on 500 Scale (US / NaCl) responds across ±30% scenario shifts.
0 ppm 500.5 ppm 1.0k ppm 490 -30% 595 -15% 700 +0% 805 +15% 910 +30%
Summary: An EC of 1400 μS/cm (1.4 mS/cm) converts to 700 ppm on the 500 NaCl scale, 896 ppm on the 640 European scale, and 980 ppm on the 700 (442) hydroponic scale.
Summary: An EC of 1400 μS/cm (1.4 mS/cm) converts to 700 ppm on the 500 NaCl scale, 896 ppm on the 640 European scale, and 980 ppm on the 700 (442) hydroponic scale.
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Formula & Mathematical Methodology: EC (μS/cm) ↔ TDS (ppm) Formula

TDS500 = ECmS × 500
TDS640 = ECmS × 640
TDS700 = ECmS × 700
ECmS = EC_μS / 1000
TDS_500 = EC_mS × 500; TDS_640 = EC_mS × 640; TDS_700 = EC_mS × 700; EC_mS = EC_μS / 1000
  • electricalConductivityMicroSiemens: Electrical Conductivity (EC) at 25°C in microsiemens per centimeter (μS/cm).

Rounding: Internal floating-point calculations run in 64-bit IEEE-754 double precision; display values round to 2–4 decimal places.

Worked Example: EC (μS/cm) ↔ TDS (ppm) Worked Example

Convert Electrical Conductivity (μS/cm & mS/cm) into TDS ppm on the 500, 640, and 700 scales.

  1. Enter the input measurement, system configuration, or astronomical parameter.
  2. Apply the standard conversion or analytical equation: TDS_500 = EC_mS × 500; TDS_640 = EC_mS × 640; TDS_700 = EC_mS × 700; EC_mS = EC_μS / 1000.
  3. Inspect the primary metric, secondary equivalents, and 3 real-time SVG graphs.
Result: Computes EC (μS/cm) ↔ TDS (ppm) via TDS_500 = EC_mS × 500; TDS_640 = EC_mS × 640; TDS_700 = EC_mS × 700; EC_mS = EC_μS / 1000.

Frequently Asked Questions

How does the Water EC (μS/cm & mS/cm) ↔ TDS (ppm 500 NaCl, 640 EU & 700 442 Scale) Converter perform the calculation?

It evaluates TDS_500 = EC_mS × 500; TDS_640 = EC_mS × 640; TDS_700 = EC_mS × 700; EC_mS = EC_μS / 1000 directly in your browser and renders three custom SVG charts in real time.

Can I solve backwards for an input parameter using Goal Seek?

Yes. Click "🎯 Goal Seek" in the results toolbar to solve backwards for any numeric input field.

Does this tool work offline?

Yes. All calculations run 100% locally in your browser with full offline PWA support.

Unit Conversions · Fluid & Chemical Conversions

Water EC (μS/cm & mS/cm) ↔ TDS (ppm 500 NaCl, 640 EU & 700 442 Scale) Converter: inputs, method, and how to read the result

Convert Electrical Conductivity (μS/cm & mS/cm) into TDS ppm on the 500, 640, and 700 scales.

Choose inputs for the case you are checking

The defaults are illustrative. Replace them with values for your case and keep the units shown beside each field.

  • Electrical Conductivity Micro Siemens: Electrical Conductivity (EC) at 25°C in microsiemens per centimeter (μS/cm).

What the calculation includes

With the default values shown, TDS on 500 Scale (US / NaCl) is 700 ppm. The calculation follows EC (μS/cm) ↔ TDS (ppm) Formula; the formula and variable definitions above show how the inputs combine.

One-input check: With the other defaults held constant, changing Electrical Conductivity Micro Siemens from 1,400 μS/cm to 1,540 μS/cm changes TDS on 500 Scale (US / NaCl) from 700 ppm to 770 ppm. This is a comparison inside the calculator's stated model, not a prediction.

Where to use caution

  • Uses official NIST Special Publication 811, IEEE/RFC systems engineering, APA psychometric, and USNO astronomical formulas.
  • Empirical metallurgy and calendar conversions represent standard reference-condition approximations.

Scope: Global NIST, IEEE, APA & Astronomical Standard Check the assumptions and limitations against your situation before relying on the estimate.

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