---
product_id: 60610029
title: "Numerically Balanced Icosahedral Dice (Single Truly Fair D20)"
brand: "tarquin"
price: "€ 0.03"
currency: EUR
in_stock: false
url: https://www.desertcart.pt/products/60610029-numerically-balanced-icosahedral-dice-single-truly-fair-d20
store_origin: PT
region: Portugal
---

# Numerically balanced D20 Ideal for probability experiments Optimized vertex sum fairness Numerically Balanced Icosahedral Dice (Single Truly Fair D20)

**Brand:** tarquin
**Price:** € 0.03
**Availability:** ❌ Out of Stock

## Summary

> 🎲 Roll with confidence—where fairness meets precision!

## Quick Answers

- **What is this?** Numerically Balanced Icosahedral Dice (Single Truly Fair D20) by tarquin
- **How much does it cost?** € 0.03 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.pt](https://www.desertcart.pt/products/60610029-numerically-balanced-icosahedral-dice-single-truly-fair-d20)

## Best For

- tarquin enthusiasts

## Why This Product

- Trusted tarquin brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Single Unique Color:** Each die comes in a distinct color, adding a personalized touch to your game night.
- • **Ready to Roll Out of the Box:** No assembly or batteries needed—just pure, fair fun from the first toss.
- • **Precision Engineered Fairness:** Meticulously balanced numbering eliminates roll bias for truly fair gameplay.
- • **Perfect for Data-Driven Gamers:** Ideal tool for probability experiments and statistical validation.
- • **Scientifically Optimized Vertex Sums:** Unique numbering scheme ensures equal probability distribution across all faces.

## Overview

This Numerically Balanced Icosahedral Dice is a single, truly fair D20 designed with a unique numbering system that balances vertex sums to minimize physical and numerical bias. Perfect for gamers and probability enthusiasts seeking scientifically optimized fairness, it comes in a single, varying color and requires no assembly or batteries.

## Description

Physical balancing of dice requires use of an isohedral polyhedron. The icosahedron, traditionally used for the d20, is such a polyhedron. Perfect physical balancing is still not possible, though, due to physical differences in numbers, small inaccuracies in molds, additional inaccuracies introduced during tumbling, and density variations due to defects like voids. In addition, it's possible to affect the roll of dice to a degree by carefully controlling the manner in which they're tossed. For these reasons, dice are more fair if they are numerically-balanced as well. For example, a void inside a die near a vertex (a point where three or more faces come together) will cause that vertex to preferentially face up when the die is tossed. The effect of such defects can be minimized by arranging the numbers such that the sum of the faces meeting at each vertex is the same. Dice are traditionally numbered such that the largest number is located opposite the smallest, next largest opposite next smallest, etc. For a d20, 20 is opposite 1, 19 opposite 2, 18 opposite 3, etc. The average value per face is half of 21, 10.5. If a die is unintentionally oblate (slightly flattened on opposing sides), the flatter regions are more likely to turn up when the die is tossed. If these two opposite numbers were 19 and 20 for example, then the die would on average roll high, since these two numbers would come up too often. Having the two numbers add to 21 avoids any such bias in the average number rolled. For this reason, the opposite-side numbering convention improves fairness. Equally important in our opinion is balancing of the vertex sums. In the standard d20 numbering, small and large numbers are distributed more-or-less evenly over the die, with the following vertex sums: 39, 47, 49, 51, 52, 52, 53, 53, 54, 56, 58, and 66. Using computer search techniques, we've managed to find a numbering with ideally-balanced vertex sum

## Features

- Numerically balanced D20
- The fairest twenty sided dice as a result
- Perfect for probability experiments
- Perfect for truly fair gaming
- single different colour - colour may vary

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Product Dimensions | 10.01 x 5.99 x 2.01 cm; 18.14 g |
| Manufacturer recommended age | 5 years and up |
| Manufacturer reference | unknown |
| Number of pieces | 1 |
| Assembly Required | No |
| Batteries Required? | No |
| Batteries included? | No |
| ASIN | B01BOVUNT6 |

## Product Details

- **Brand:** Tarquin
- **Item weight:** 18 g
- **Theme:** Number
- **Number of pieces:** 1
- **Shape:** Hexahedron

## Images

![Numerically Balanced Icosahedral Dice (Single Truly Fair D20) - Image 1](https://m.media-amazon.com/images/I/71mrha0OFDL.jpg)

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.pt/products/60610029-numerically-balanced-icosahedral-dice-single-truly-fair-d20](https://www.desertcart.pt/products/60610029-numerically-balanced-icosahedral-dice-single-truly-fair-d20)

---

*Product available on Desertcart Portugal*
*Store origin: PT*
*Last updated: 2026-05-18*