Formula: erg → joule
J = erg × 1 × 10⁻⁷
Example: 5,000,000 ergs
J = 5,000,000 × 1e-7 = 0.5 J
Formula: joule → erg
erg = J × 1 × 10⁷
Example: 2.3 J
erg = 2.3 × 10,000,000 = 23,000,000 ergs
Why convert ergs to joules?
The erg is part of the CGS (centimeter–gram–second) system and appears in older physics literature, astrophysics energy outputs, and some chemistry tables. Modern SI work uses the joule (J), so this conversion is often needed to compare values or plug them into SI-only formulas.
FAQ
1. Is this conversion exact?
Yes. The relationship 1 erg = 1×10⁻⁷ J is defined, not measured.
2. Can I enter scientific notation?
You can type big numbers (like 3e7) in most browsers’ number fields, but if your browser doesn’t accept it, just enter the plain number and the tool will convert it.
3. What about “erg·s” (erg second) I saw in a table?
That’s a different physical quantity (action). This page is strictly for energy: erg ↔ joule.
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
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Formula (extracted text)
J = erg × 1 × 10⁻⁷ Example: 5,000,000 ergs J = 5,000,000 × 1e-7 = 0.5 J
Formula (extracted text)
erg = J × 1 × 10⁷ Example: 2.3 J erg = 2.3 × 10,000,000 = 23,000,000 ergs
Variables and units
- No variables provided in audit spec.
Sources (authoritative):
- NIST — Weights and measures — nist.gov · Accessed 2026-01-19
https://www.nist.gov/pml/weights-and-measures - NIST — SI units — nist.gov · Accessed 2026-01-19
https://www.nist.gov/pml/owm/metric-si/si-units
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
- Initial audit spec draft generated from HTML extraction (review required).
- Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
- Confirm sources are authoritative and relevant to the calculator methodology.