Skip to main content

Calorie (th) to Attojoule (cal (th) to aJ) Converter & Formula

Rate this converter 0 of 0 ratings
Live Conversion • ISO 80000-5:2019 Certified
1 Calorie (th) = 4.184 × 10¹⁸ Attojoule
1 cal (th) = 4.184 × 10¹⁸ aJ • 1 aJ = 2.390057 × 10⁻¹⁹ cal (th)
Calorie (th) to Attojoule: One Calorie (th) is equal to 4.184 × 10¹⁸ Attojoules.
Certified Authority Value
4184000000000000000.00000000
aJ
Exact: 1 aJ ≡ 2.3900573614 × 10⁻¹⁹ cal (th)
cal (th)
cal (th)
aJ
aJ 4.184 × 10¹⁸
Conversion Formula
To convert Calorie (th) to Attojoule, multiply by 4.184 × 10¹⁸
cal (th) × 4.184 × 10¹⁸ = aJ

Calculation: 1 cal (th) × 4.184 × 10¹⁸ = 4.184 × 10¹⁸ aJ

Common Calorie (th) to Attojoule Calculations

Quick-lookup reference table showing calculated equivalents for standard increments between Calorie (th) (cal (th)) and Attojoule (aJ).

Tap any row to calculate
Attojoule to Calorie (th): Reciprocal Summary

Real-World Context & Everyday Benchmarks

Tap to load into converter

To help contextualize these units in everyday life, science, and engineering, here are verified real-world reference points for Calorie (th) (cal (th)) and Attojoule (aJ):

Calorie (th) References:

  • Thermochemical calorie standard defined as exactly 4.184 joules 1 cal_th

Attojoule References:

  • Theoretical minimum switching energy required to toggle a magnetic nanoscopic memory bit 1 aJ
ISQ Dimension: [M L² T⁻²] Coherent SI Unit: joule (J) Chemical Engineering, Solutions & Physical Chemistry

How to Convert Calorie (th) to Attojoule

Converting Calorie (th) (cal (th)) to Attojoule (aJ) is a core calculation in Energy and Work, which quantifies the physical capacity to perform mechanical work, generate heat, or emit electromagnetic radiation. Because Calorie (th) represents a larger magnitude than Attojoule, converting from cal (th) to aJ expands the numerical figure. Exactly 1 Calorie (th) encompasses 4.184 × 10¹⁸ Attojoule. To convert any quantity, multiply the value in Calorie (th) by 4.184 × 10¹⁸.

Direct Factor1 cal (th) = 4.184 × 10¹⁸ aJ
Inverse Ratio1 aJ = 2.390057 × 10⁻¹⁹ cal (th)
Conversion ScaleDirect Proportional Magnitude Expansion
First-Principles SI Derivation ProofNIST SP 811 / ISO 80000 Compliance

Mathematical Conversion Derivation via Coherent SI Base Unit

Under the International System of Quantities (ISQ), dimensional conversion between non-SI units is rigorously resolved by bridging through the coherent SI base unit (joule (J)) without arbitrary rounding:

Vtarget=Vsource×(ksource→SIktarget→SI)V_{\text{target}} = V_{\text{source}} \times \left( \frac{k_{\text{source} \to \text{SI}}}{k_{\text{target} \to \text{SI}}} \right)
Universal Dimensional Conversion Law (ISO 80000 / NIST SP 811)
1. Source SI Bridge (ksource):1 cal (th) = 4.184 joule (J)
2. Target SI Bridge (ktarget):1 aJ = 1 × 10⁻¹⁸ joule (J)
Step-by-step substitution for Calorie (th) → Attojoule:V(aJ) = V(cal (th)) × ( 4.184 / 1 × 10⁻¹⁸ ) = V(cal (th)) × 4.184 × 10¹⁸
Mathematical FormulaValue in Attojoule = Value in Calorie (th) × 4.184 × 10¹⁸Direct computational formula applied for standard conversion.
Worked Example

For an engineering input of 75 cal (th), applying the conversion factor yields exactly 3.138 × 10²⁰ aJ. At larger operational scale, 2500 Calorie (th) corresponds to 1.046 × 10²² aJ.

Inverse check: 1 aJ = 2.390057 × 10⁻¹⁹ cal (th).

Understanding Calorie (th) and Attojoule

Calorie (th)

cal (th)
Standard Unit

A Calorie (th) (cal (th)) is a recognized unit for energy and work.

Applications & Practical Context

In practical energy terms, a thermochemical calorie standard defined as exactly 4.184 joules equals 1 cal_th.

Physical Setup

An energy quantity of 1 cal (th) corresponds to 4.184 J (performing 4.184 joules of work or heat transfer).

Conversion to SI Unit: joule (J)
1 cal (th) = 4.184 J

Attojoule

aJ
SI Submultiple

An Attojoule (aJ) is a decimal submultiple of the SI-derived unit for energy and work.

Applications & Practical Context

In practical energy terms, a theoretical minimum switching energy required to toggle a magnetic nanoscopic memory bit equals 1 aJ.

Physical Setup

An energy quantity of 1 aJ corresponds to 1 × 10⁻¹⁸ J (performing 1 × 10⁻¹⁸ joules of work or heat transfer).

Conversion to SI Unit: joule (J)
1 aJ = 1 × 10⁻¹⁸ J

Domain Metrology & Engineering Applications

Governing Law & Equation

First Law of Thermodynamics (Conservation of Energy: ΔU = Q - W)

Measurement Instrumentation

Rigorously quantified in laboratory and field settings using isoperibol bomb calorimeters, optical laser pulse joulemeters, and digital revenue-grade electric energy meters.

Primary Industry Sectors

Applied across electric power utility metering, thermal energy storage design, chemical plant process enthalpies, and ballistic impact engineering under international metrology standard ISO 80000-5:2019, NIST SP 811.

Physical Orders of Magnitude & Laboratory Reference Benchmarks

Physical Phenomenon / Engineering ReferenceReference ValueConverted to Attojoule
Thermochemical calorie standard defined as exactly 4.184 joules1 cal_th4.184 × 10¹⁸ aJ
Institutional Metrology & Standard Authority:

Formulas, conversion coefficients, and base definitions on this page strictly adhere to the ISO 80000-5:2019, NIST SP 811 and the BIPM SI Brochure (9th Edition). Governed by First Law of Thermodynamics (Conservation of Energy: ΔU = Q - W) under ISO 80000 dimensional vector [M L² T⁻²].

Multi-Variable Engineering Bridge Grid Energy & Industrial Work

Continuous Power & Operating Duration Bridge (kWh • Megajoules • BTU • Average Power • Battery Runtime)

Bridge instantaneous work rate [M L² T⁻³] and accumulated energy consumption [M L² T⁻²] over operational shifts and duty cycles via the work-power equation E = P × t.

E = P × t
Live Calculated Bridge Equivalent:
1 cal (th) at 1-Hour Standard Benchmark Runtime = 0.004184 kWh
Equals 0.01506 MJ • 14.28 BTU • 15062.4 J
Utility Standard
0.004184
kWh
Kilowatt-Hours
SI Metric Energy
0.01506
MJ
Megajoules
HVAC & Thermal
14.28
BTU
British Thermal Units
SI Base Unit
15062.4
J
Joules
Grid Power Scale
4.184 × 10⁻⁶
MWh
Megawatt-Hours
Mechanical Work
0.005611
hp·h
Horsepower-Hours
  1. 1. Normalize Input to SI Base Unit (W):
    P = 1 cal (th) × 4.184 = 4.184 W
  2. 2. Apply Engineering Parameter (t):
    Selected condition: 1-Hour Standard Benchmark Runtime at t = 3600 Seconds / Hours
  3. 3. Execute Governing Physical Law in SI Units:
    E = P × t = (4.184) × (3600) = 15062.4 J
  4. 4. Convert to Standard Engineering Units:
    • kWh: 15062.4 × 2.7778 × 10⁻⁷ = 0.004184 kWh (Kilowatt-Hours) • MJ: 15062.4 × 1 × 10⁻⁶ = 0.01506 MJ (Megajoules) • BTU: 15062.4 × 0.0009478 = 14.28 BTU (British Thermal Units) • J: 15062.4 × 1 = 15062.4 J (Joules) • MWh: 15062.4 × 2.7778 × 10⁻¹⁰ = 4.184 × 10⁻⁶ MWh (Megawatt-Hours) • hp·h: 15062.4 × 3.7251 × 10⁻⁷ = 0.005611 hp·h (Horsepower-Hours)
Explore Full Power Converter →
Engineering Substance / Operating Standard Parameter Value (Seconds / Hours) Reference State / Condition Typical Industrial & Engineering Application
1-Second Pulse (Inrush / Circuit Breaker) 1 1.0 second Motor inrush peak & capacitor discharge
1-Minute Short Cycle (Microwave / Lift) 60 60 seconds Elevator transit & commercial appliance duty
1-Hour Standard Benchmark Runtime 3600 3,600 seconds Standard utility kilowatt-hour energy basis
8-Hour Factory Shift (Industrial Machinery) 28800 8.0 hours Single industrial production line workday
24-Hour Continuous Day (Data Center / Pump) 86400 24.0 hours Always-on server racks & municipal water treatment
7-Day Continuous Week (Chemical Refining) 604800 168.0 hours Continuous manufacturing process plant run
30-Day Monthly Billing Cycle 2592000 720.0 hours Electric utility meter billing period
365-Day Annual Base Load Operation 3.1536 × 10⁷ 8,760 hours Grid generator annual capacity factor calculation
Embed
Need this Calorie (th) to Attojoule calculator on your website, lab portal, or research blog?
Free HTML Widget 100% Responsive Zero Cookie Tracking
Notice a calculation discrepancy, rounding error, or glitch?
Help us maintain 100% scientific precision and report any issues directly to engineering.

Frequently Asked Questions

There are exactly 4.184 × 10¹⁸ attojoules (aJ) in 1 calorie (th) (cal (th)). To calculate larger amounts manually, simply multiply your total number of calories (th) by the conversion multiplier of 4.184 × 10¹⁸.

The mathematical formula to convert calories (th) to attojoules is: [value] * 4.184 × 10¹⁸ = attojoules. Rather than doing the math manually, you can use our high-precision online calculator to process this exact equation instantly without rounding errors.

To perform the reverse calculation from attojoules back to calories (th), you must divide your starting value by 4.184 × 10¹⁸. Our bidirectional tool automatically computes this inverse equation the moment you type into the attojoule input field.

1 Calorie (th) is larger than 1 Attojoule. Specifically, 1 Calorie (th) equals exactly 4.184 × 10¹⁸ attojoules, making it 4.184 × 10¹⁸ times larger (a difference of 18.62 orders of magnitude). Therefore, quantities expressed in attojoules require a larger numerical value to represent the same physical amount.

A typical thermochemical calorie standard defined as exactly 4.184 joules measures 1 cal_th, which corresponds to 4.184 × 10¹⁸ Attojoule (Attojoule).

Exactly 4.18400 × 10¹⁸ Attojoule correspond to one Calorie (th). Written as an identity: 1 cal (th) = 4.18400 × 10¹⁸ aJ.

Use the direct multiplication equation: V(aJ) = V(cal (th)) × 4.18400 × 10¹⁸.

The reverse translation utilizes the reciprocal equation: V(cal (th)) = V(aJ) × 2.39006 × 10⁻¹⁹.

Attojoules (10⁻¹⁸ Joules) parameterize sub-molecular chemical bond energies, serving as the microscopic correlate to bulk gram-scale water heating (calories).