How to Practice
FIELD GUIDE / START HERE
Choose a scale, work through a few marks, then look at what you learned. A short, careful set is a useful place to start.
Set up your practice bench
- Choose Inches or Metric. Inches can be divided into halves, quarters, eighths or sixteenths. Metric questions always show 1 mm spaces, with the larger numbers labelling centimetres.
- Choose the smallest inch mark or the metric answer unit. If you are new to fractions, start with 1/2 inch. For metric practice, decide whether to answer in mm or cm before you begin.
- Choose an exercise. Read the mark asks you to name a position. Place the mark asks you to move a marker to the requested measurement.
- Choose 5, 10 or 20 questions. Nothing is timed. Press Start new set to apply the settings. Starting again replaces an unfinished set, but its already answered questions remain in your local totals.
Read the mark
Find the last whole inch or centimetre before the orange pointer. Count the small spaces between that numbered mark and the pointer. Combine them, then enter the measurement in the requested unit.
For inches, type 3/4 for a fraction or 1 3/4 for a mixed number. A decimal such as 1.75 is also accepted. Do not type the unit into the answer box; the exercise already shows it. Use a decimal point, not a comma.
Place the mark
Read the target measurement above the diagram. Tap or click the ruler to move the orange marker, or use the slider below it. The marker snaps to the ruler's smallest division. Press Check position when you are ready.
With a keyboard, focus the slider and use the arrow keys for one-division steps. Home and End move to the ends of the scale in browsers that support those standard slider controls. The current selected measurement is displayed beside the label and announced through the slider's accessible value.
Use the steps when you need them
Show the steps explains the current mark. If you open it before your first answer, the question is recorded as guided. First-try accuracy includes guided answers; the guided count stays visible beside it so the result has context.
A wrong answer reveals the correct reading and its steps. You can try the same mark again or continue. Correcting it is good practice, but it does not change the original first-try score. At the end, Retry missed marks makes a separate practice set from the marks you missed.
Make the ruler easier to see
Use 2× detail to enlarge the diagram, then scroll horizontally inside its frame. Fit to screen restores the whole ruler. The page itself stays within your screen. A larger diagram does not change any measurement or answer.
Understand your logbook
The local logbook keeps overall answered questions, first-try correct answers, completed standard sets, the best within-set streak and six recent completed sets. A retry set adds new practice questions to the overall totals but is not added to the completed-set history. There are no public rankings or cross-device accounts.
Browser storage can be disabled, cleared or removed when private browsing ends. The tool still works if it cannot save. Clear saved progress asks for a second click, then clears the logbook and starts the current practice settings again.