---
title: "LDPE — density, melting point and properties"
description: "LDPE has a density of 920 kg/m³ (910–930). Melting point, strength, conductivity, what it is used for, and whether it floats, rusts or is magnetic."
url: https://atoneplace.net/material/ldpe/
site: "At One Place"
---

# LDPE

**Density of LDPE: 920 kg/m³ (910–930)**

0.92 g/cm³ · 57.4 lb/ft³

Chemically the same polymer as HDPE, but the chains are branched so they pack badly — that is the whole difference, and it produces a material four times less stiff, much clearer, and far easier to tear. Branching is why LDPE film clings and stretches while HDPE film crackles. It melts around 110 °C, low enough that a carrier bag left on a hot lamp will pool.

## Properties

- **Density:** 920 kg/m³ (910–930) — 0.92 g/cm³
- **Melting range:** 105–115 °C
- **Tensile strength:** 8–20 MPa
- **Young's modulus:** 0.25 GPa
- **Thermal conductivity:** 0.33 W/(m·K)
- **Thermal expansion:** 180 µm/(m·K)
- **Floats in water:** Yes
- **Magnetic:** No

## What it is used for

- Carrier bags and cling film
- Squeeze bottles
- Wire and cable insulation
- Damp-proof membrane sheeting

## How it compares

*Water is 1,000 kg/m³. Anything with a shorter bar than water floats in it.*

- air: 1.2 kg/m³
- expanded polystyrene foam: 20 kg/m³
- rigid polyurethane foam: 40 kg/m³
- LDPE: 920 kg/m³
- Water — the float line: 1,000 kg/m³
- tungsten: 19,250 kg/m³
- gold: 19,300 kg/m³
- platinum: 21,450 kg/m³

*Water is 1,000 kg/m³. Anything below that floats.*

| Material | Density | Relative to water |
| --- | --- | --- |
| rigid polyurethane foam | 40 kg/m³ | 0.04× |
| expanded polystyrene foam | 20 kg/m³ | 0.02× |
| air | 1.2 kg/m³ | 0.00× |
| LDPE ← | 920 kg/m³ | 0.92× |
| platinum | 21,450 kg/m³ | 21.45× |
| gold | 19,300 kg/m³ | 19.30× |
| tungsten | 19,250 kg/m³ | 19.25× |

## Does it rust?

LDPE contains no iron, so it cannot rust. Whether it degrades depends on the material, not on oxidation.

## Is it magnetic?

LDPE is not a metal and has no ferromagnetic response.

## Common questions

### What is the density of LDPE?

920 kg/m³ (910–930), or 0.92 g/cm³.

### Does LDPE float?

Yes. At 920 kg/m³ it is less dense than water's 1,000.

### Is LDPE magnetic?

LDPE is not a metal and has no ferromagnetic response.

## Related pages

- [Does LDPE float?](https://atoneplace.net/does-it-float/ldpe/)
- [PLA](https://atoneplace.net/material/pla/)
- [ABS](https://atoneplace.net/material/abs/)
- [Acrylic (PMMA)](https://atoneplace.net/material/acrylic/)
- [Polycarbonate](https://atoneplace.net/material/polycarbonate/)
- [Polypropylene](https://atoneplace.net/material/polypropylene/)
- [PTFE](https://atoneplace.net/material/ptfe/)
- [Rigid PVC](https://atoneplace.net/material/pvc-rigid/)
- [HDPE](https://atoneplace.net/material/hdpe/)

## Sources

- Typical range compiled from manufacturer specifications — At One Place (/about/)