Soroban (Japanese Abacus)

Soroban? What Is It?

The soroban, commonly known as the "Japanese Abacus," consists of an odd number of columns or rods, each with beads: one bead valued at five, called the go-dama (五玉, ごだま, "five bead"), and four beads each valued at one, called ichi-dama (一玉, いちだま, "one bead"). Each set of beads on every row is separated by a horizontal bar called the reckoning bar. The number and size of beads per rod make a standard 13-rod soroban much more compact than a standard-sized Chinese abacus (or suanpan) of comparable numerical capacity.

The number of rows on a soroban is always odd and never fewer than seven. The most common models usually feature thirteen rods, but practical or standard models often extend to 17, 21, or even 27 rods, allowing for calculations with more digits or the representation of multiple numbers simultaneously. Each row represents a digit, and having more rods enables representing larger numbers either as single numbers or during calculations.

Why Choose a Soroban?

We are often asked: why learn the soroban? What are its benefits?

Learning the soroban offers numerous advantages for children:

• Helps develop concentration and patience.
• Fosters an intuitive understanding of numbers through their concrete representation on the soroban.
• Enhances memory skills.
• Demonstrates the concept of decimals and the progression of units by tens physically: the order of magnitude is represented intuitively.
• Enables instant addition and subtraction when numbers are set on the abacus.
• Builds confidence in calculation processes by allowing them to be visually tracked in action.
• Allows children to break down operations into manageable steps.
• Uses a left-to-right calculation method, facilitating quick estimation and rounding.
• Works on the decimal system rather than fractional systems, easing progression into numerical systems.
• Develops valuable mental arithmetic skills.
• Stimulates right-brain development.
• Represents large numbers simply and easily.
• Provides a sense of achievement as skills improve.
• Supports the development of fine motor skills.

The soroban is a powerful calculation instrument, but especially serves as an educational tool in school learning and early math awareness.

Soroban learning is particularly recommended for elementary school children, from first to fifth grade.

Second and third grades (CE1 and CE2 in the French system) are likely the optimal period to introduce the soroban.

Unlike calculators, the soroban requires the child's active thinking: it offers an intuitive grasp of arithmetic operations and helps memorize addition and multiplication tables. Performing a calculation requires decomposing the operation, helping children better assimilate arithmetic concepts.

After using the soroban for a while, a child can perform mental calculations of higher magnitude almost instinctively. Eventually, the operational techniques of the abacus can be applied mentally, a skill known as Anzan: the child fully mastering the soroban can then perform complex mental calculations without a calculator.

Most mathematical operations are possible with the soroban, including addition, subtraction, and even multiplication and division (with solid knowledge of multiplication tables). However, to handle arithmetic operations involving multiplication and division, you will need a large soroban (at least 13 columns), especially when working with decimal numbers!

The soroban is highly praised by mathematicians for its educational role in learning basic arithmetic. It allows practicing math games, turning learning into play. The soroban is increasingly popular in elementary education for teaching mathematics. It is an effective didactic tool proven in numerous educational systems and millions of young learners worldwide for mastering arithmetic.

Basic operations (addition and subtraction) are easy to learn; within minutes, your child will understand the soroban notation and how to use it for calculations. Addition is very straightforward, and subtraction simply reverses the addition process.

Multiplication requires a slightly different logic but remains simple and quickly becomes an enjoyable calculation game for children.

The History of the Soroban

A unique feature that distinguishes the soroban from its Chinese relative is the absence of two beads: it has only one five-value bead (instead of two) and four unit beads (instead of five).

The number of beads is identical to the Roman abacus, which had four beads below and one bead above.

Most historians agree that its roots trace back to the importation of the Chinese abacus to Japan via the Korean peninsula around the 14th century, when the suanpan arrived in Japan as the soroban (with bead modifications to ease use). At that time, it had two heaven beads and five earth beads. However, the soroban was not widely used until the 17th century, though Japanese merchants had been using it since its introduction.

During the soroban’s construction evolution, the number of beads began to decrease. Around 1850, one heaven bead was removed from the suanpan configuration of two heaven beads and five earth beads. This new Japanese design coexisted with the suanpan until the early Meiji period, after which the suanpan fell completely out of use in Japan. In 1891, Irie Garyū further removed one unit bead, creating the modern configuration of one heaven bead and four earth beads. This configuration was reintroduced in 1930 and gained popularity in the 1940s.