Neutron
A neutron is a type of subatomic particle found in atomic nuclei, carrying no electric charge and playing a key role in holding nuclei together.
1.675 × 10⁻²⁷ kgMassBeyond the eye
Neutron vs Proton
What are they, and what does the difference actually look like?
Two things. One honest scale.
Meet the pair
What these two things are
Proton
A proton is a positively charged particle found in the nucleus of atoms, made up of quarks.
1.673 × 10⁻²⁷ kgMassNeutron and Proton have approximately the same mass.
Bar length measures mass, not physical size.
Measurements, assumptions & sources +
Neutron
A free neutron’s mass. It is a quantum particle with internal structure, not a little solid sphere.
NIST — 2022 CODATA fundamental constants
The marked mass is calibrated. Unmeasured illustration details are representative.
Proton
Twice the approximately 0.8409 fm charge radius. The charge distribution has no hard boundary; the illustration is schematic.
NIST — 2022 CODATA fundamental constants
The marked mass is calibrated. Unmeasured illustration details are representative.
Change the comparison
Put something else beside it.
Measurement details
Why these numbers?
The visual compares mass with mass. The records below preserve each value’s basis and caveats.
Neutron
1.675 × 10⁻²⁷ kgMass · measured constant
A free neutron’s mass. It is a quantum particle with internal structure, not a little solid sphere.
Proton
1.673 × 10⁻²⁷ kgMass · measured constant
Twice the approximately 0.8409 fm charge radius. The charge distribution has no hard boundary; the illustration is schematic.
- Comparing
- Mass ↔ Mass
- Relative size
- The two selected measurements are approximately equal.
How to read the visual
The labelled spans and stored measurements determine the scale; unmeasured illustration details do not.
- Neutron is labelled measured constant; treat the displayed value as a comparison anchor rather than false precision.
- Proton is labelled measured constant; treat the displayed value as a comparison anchor rather than false precision.
There’s always another scale
Follow your curiosity.
Fundamental physicsNeutron1.675 × 10⁻²⁷ kgA neutron is a type of subatomic particle found in atomic nuclei, carrying no electric charge and playing a key role in holding nuclei together.Fundamental physicsProton1.682 fmA proton is a positively charged particle found in the nucleus of atoms, made up of quarks.
Fundamental physicsPlanck length1.616 × 10⁻³⁵ mThe Planck length is a scale formed from fundamental physical constants.
MicroscopicHydrogen atom105.8 pmA hydrogen atom is the simplest neutral atom, with one proton in its nucleus and one electron around it.
MicroscopicDNA double helix2 nmDNA is the molecule that stores hereditary information in living organisms.Side by side
Another point of view.
