Triple-Beam Balance Reader
Drag the three riders into their notches, balance the pointer at zero, and read the rear, middle and front beams as a single mass to 0.1 g — free and 100% in your browser.
How to Read a Triple-Beam Balance
ToolsPix Triple-Beam Balance Reader is a free, interactive triple-beam balance simulator that runs entirely in your browser. It is drawn with lightweight SVG and native JavaScript, so there is no software to install, no account to create, and nothing is ever uploaded to a server.
Why use the ToolsPix Triple-Beam Balance Reader?
- Completely free with no sign-up, watermark, or usage limit.
- Runs entirely in your browser — nothing you do is ever sent to a server.
- Drag the rear, middle and front riders to see how the three beams add to a single mass.
- Breaks every reading into the 100 g, 10 g and 0.1 g beams so you can see where each digit comes from.
- Includes a balance pointer and a practice mode with instant tolerance-aware scoring.
Steps to read a triple-beam balance
Place the object on the pan, then move the riders from the largest beam to the smallest. Slide the rear (100 g) rider one notch at a time until the pointer drops below zero, then back it off one notch. Do the same with the middle (10 g) rider. Finally slide the front (0.1 g) beam until the pointer rests exactly on zero. Add the three beam values together — for example 300 g + 40 g + 7.4 g = 347.4 g — to get the total mass. Switch to Practice for a random reading to check yourself, and press Reset to start again. Once the page is loaded, the tool also works completely offline.
FAQ
How do I read a triple-beam balance?
Read the three beams from the largest to the smallest and add the values together. First note the notch the rear 100 g rider sits in, then the middle 10 g rider, then read where the front rider points on the 0 to 10 g scale. The total mass is the sum of all three beams — for example 300 g plus 40 g plus 7.4 g gives 347.4 g. Always make sure the pointer rests at zero before you trust the reading.
What is the precision of a triple-beam balance?
A typical laboratory triple-beam balance reads to the nearest 0.1 g. The rear and middle beams move in fixed notches of 100 g and 10 g, while the front beam slides continuously and is graduated in 0.1 g divisions, so the smallest amount you can confidently distinguish is one tenth of a gram. You may estimate a final digit between the front-beam marks, but 0.1 g is the guaranteed resolution of the instrument.
What is a rider and a notch on a triple-beam balance?
A rider — sometimes called a poise or weight — is the sliding mass that you move along each beam. A notch is one of the grooved seats on the rear and middle beams that the rider drops into so it cannot drift between values. The rear and middle riders must always sit squarely in a notch, while the front rider slides freely along its scale. Reading the balance means noting the value at each rider and adding the three beams together.
Why must the pointer be at zero before reading?
The pointer at the end of the beam shows whether the riders balance the object on the pan. If the pointer sits above or below the centre mark, the masses on the beams do not yet equal the mass of the object, so any reading would be wrong. Move the riders until the pointer settles exactly on the zero line — only then does the sum of the three beams equal the true mass on the pan.
Is the triple-beam balance reader free and does it work offline?
Yes. The triple-beam balance reader is completely free with no sign-up, and every calculation runs locally in your browser with JavaScript. Nothing is uploaded to any server, and once the page has loaded it also works completely offline.