Number Line Generator
Set the ends and the major and minor steps as whole numbers, fractions, mixed numbers or decimals, and every tick is labelled from exact fraction arithmetic, so thirds read 1/3 and 2/3 and ten steps of 0.1 land on exactly 1. Drop labelled pins and drag them, or move them from tick to tick with the arrow keys; draw jumps labelled with their signed lengths; mark open or closed intervals and rays; and add freehand marks or a ring round a value. Download the line as an SVG, a one-page PDF on Letter or A4, or a JSON project you can open here again. The whole line is also written out in words under the drawing.
Click or tap the line to drop a pin on the nearest tick. Drag a pin to move it, or focus it and use the arrow keys (Shift or Page keys for major ticks).
This is an example line. Change the settings, load a starting point below, or press Clear items to start your own.
In words
- Number line from −3 to 4, major ticks every 1, minor ticks every 1/2, 15 ticks.
- Labels: −3, −2, −1, 0, 1, 2, 3, 4.
- Pin A: −2.
- Pin B: 3.
- Jump 1: from −2 to 3, 3 − (−2) = 5.
- Interval 1: [−1/2, 2): −1/2 ≤ x < 2, closed at −1/2, open at 2.
- Mark 1: a freehand mark of 37 points around 0.
Type whole numbers, fractions like 3/4, mixed numbers like 1 1/2 or decimals like 0.25. The minor step has to divide the major step, and a line draws up to 400 ticks.
Pins
Each pin has a label and an exact value. The − and + buttons move a pin to the next tick; a typed value places it exactly, even between ticks. Up to 40 pins.
Jumps
A jump is an arc from one value to another, labelled with its signed length. Repeat draws equal jumps one after another, so 0 to 3/4 repeated 4 times counts on to 3.
- Jump 1: from −2 to 3, 3 − (−2) = 5.
Intervals
A closed end is a filled circle and includes its value; an open end is a hollow circle and leaves it out. Leave one end blank for a ray that runs off the line.
- Interval 1: [−1/2, 2): −1/2 ≤ x < 2
Drawing
Freehand marks sit on the drawing, not on numbers, so they stay put when the range changes. Draw them in Draw mode, or ring a value here. Up to 60 marks and 6,000 points in all.
- Mark 1: a freehand mark of 37 points around 0.
Starting points
Each loads a whole line; Undo brings back the one you had.
Common questions
- How do I make a number line with fractions?
- Set From and To, then type the major step as a fraction, such as 1/4 for quarters, and a minor step that divides it, such as 1/8, or leave the minor step blank for none. Choose Fractions, Mixed or Decimals under Labels as. Every label is worked out in exact fractions, so 0 to 1 in quarters reads 0, 1/4, 1/2, 3/4, 1, and 0 to 2 in thirds as mixed numbers reads 0, 1/3, 2/3, 1, 1 1/3, 1 2/3, 2.
- Can the labels show decimals instead of fractions?
- Yes: choose Decimals. A value whose decimal ends, such as 1/4 or 1/8, shows as 0.25 or 0.125, worked out exactly, so tenths read 0.1, 0.2, 0.3 and never 0.30000000000000004. A value whose decimal never ends, such as 1/3, or one that needs more than 12 decimal places, keeps its fraction label, and a note under the drawing says so.
- How do I show jumps or hops on a number line?
- Pick Jump, then click or tap where the jump starts and where it lands; both ends snap to the nearest tick. Or type From, To and Repeat under Jumps: 0 to 3/4 repeated 4 times draws four equal arcs that stop at 3/4, 1 1/2, 2 1/4 and 3. Each arc is labelled with its signed length, such as +5 or −3/4, and the text under the drawing writes out the subtraction, such as 3 − (−2) = 5.
- How do I draw an open or closed circle for an inequality?
- Under Intervals, type the two ends and choose Closed or Open for each. A closed end is a filled circle that includes its value; an open end is a hollow circle that leaves it out. Leave one end blank for a ray that runs off the line with an arrow, so x > 2 is a left end of 2, open, with the right end blank. The text gives the interval notation and the inequality, such as [−1/2, 2): −1/2 ≤ x < 2.
- Can I move the pins with a keyboard or on a phone?
- Yes. Each pin on the drawing is a slider: focus it and the arrow keys move it to the next tick, Shift with an arrow or Page Up and Page Down move it to the next major tick, and Home and End go to the first and last ticks. The Pins list under the settings has − and + buttons and a value field for every pin, sized for a finger, and a typed value places a pin exactly, even between ticks.
- What size does the PDF print at?
- One page, US Letter or A4, landscape or portrait, chosen next to the PDF button. The drawing fills the width inside half-inch margins, 10 inches across on Letter landscape, and its lines and text are vectors, so they print sharp. The PDF font has no true minus sign, so negative labels print with a hyphen, and a pin-label character the font lacks prints as a question mark, with the message saying how many; the SVG keeps them.
- Is there a limit on ticks, pins or marks?
- A line draws up to 400 ticks; asking for more gives the count and asks for a larger step or a shorter range. A line holds up to 40 pins, 40 jumps, 12 intervals and 60 freehand marks of up to 600 points each, 6,000 points in all. Values can reach 1,000,000,000 either side of zero, with denominators up to 1,000,000.
- Does zooming change the numbers?
- No. Zoom, from 100% to 400%, only widens the drawing on screen so close ticks are easier to see and drag. Every value stays the fraction it was, and the SVG and PDF are drawn at the same size whatever the zoom.
- Where is my number line saved?
- In this browser, and in any JSON file you download; nothing is uploaded. Open JSON loads a saved project back for editing and refuses a file that is not a project saved by this page, is larger than 1 MB, or goes past the limits above. Start over at the top of the page forgets the copy kept in this browser.
Tick, pin and jump labels are exact fractions, worked out in whole-number arithmetic inside the range you set, so a third stays 1/3 and never drifts to 0.333. Where a tick, pin or mark lands on screen or on paper is limited by pixel and printer precision.