Cable tie sizes are defined by four numbers: length, width, tensile strength, and maximum bundle diameter. Lengths run from about 80 mm (3″) for small electronics up to 1,200 mm (48″) for industrial bundles; widths run from 2.5 mm to 12.7 mm, and wider ties carry higher tensile ratings. To pick a size: measure your bundle’s diameter, choose a tie whose rated bundle diameter is larger, then match the tensile rating to the load. The chart below covers every common size — and the rest of this guide explains how to read it, how to measure your bundle, and the sizing mistakes that make ties fail.
As a nylon cable tie manufacturer, we mold these sizes every day and test them in our own QC lab, so the guidance here comes from production experience, not just catalog data.
The four numbers that define a cable tie size
- Length — measured from the tip of the head to the end of the tail, in mm or inches. Part of the length is consumed by the head and the wrap itself, so the usable (“effective”) length is always a little shorter than the stated one.
- Width — the width of the strap. This is the main driver of strength: a 2.5 mm miniature tie and a 12.7 mm extra-heavy-duty tie can be the same length but differ in tensile rating by a factor of ten.
- Tensile strength — the minimum straight-pull load the closed loop holds before failure, stated in lbs or kg (e.g. 18 lbs / 8 kg for miniature, 250 lbs / 114 kg for extra heavy duty). Ratings follow the loop tensile test method in the UL 62275 standard.
- Maximum bundle diameter — the largest bundle the tie physically closes around. As a quick estimate: max bundle diameter ≈ effective length ÷ π (3.14). A 300 mm tie with roughly 280 mm of effective length closes around a bundle of about 89 mm (3.5″).
Strap thickness (typically 1–2 mm) matters too — thinner straps flex into tight spaces, thicker ones resist stretch — but for selection purposes the four numbers above decide the size.
Cable tie size chart (mm and inches)
The table below lists the standard nylon cable tie sizes used across the industry. Figures are typical catalog values for Nylon 66 ties; exact ratings vary by product line, so confirm the datasheet for your specific tie before a load-critical application.
| Length | Width | Tensile strength | Max bundle dia. | Typical use |
|---|---|---|---|---|
| 100 mm / 4″ | 2.5 mm | 18 lbs / 8 kg | ~22 mm / 0.9″ | Small electronics, PC builds, crafts |
| 150 mm / 6″ | 3.6 mm | 40 lbs / 18 kg | ~35 mm / 1.4″ | Desk and TV cable runs, light wiring |
| 200 mm / 8″ | 4.8 mm | 50 lbs / 22 kg | ~50 mm / 2″ | Home and panel wiring, garden use |
| 250 mm / 10″ | 4.8 mm | 50 lbs / 22 kg | ~65 mm / 2.6″ | Automotive looms, medium bundles |
| 300 mm / 12″ | 4.8–7.6 mm | 50–120 lbs / 22–54 kg | ~85 mm / 3.4″ | The all-rounder: IT, workshop, outdoor |
| 380 mm / 15″ | 7.6 mm | 120 lbs / 54 kg | ~110 mm / 4.3″ | Conduit, hose, trunking |
| 450 mm / 18″ | 7.6–9.0 mm | 120–175 lbs / 54–79 kg | ~130 mm / 5.1″ | Construction, HVAC, signage |
| 530 mm / 21″ | 9.0 mm | 175 lbs / 79 kg | ~155 mm / 6.1″ | Large cable trays, ducting |
| 760 mm / 30″ | 9.0–12.7 mm | 175–250 lbs / 79–114 kg | ~225 mm / 8.9″ | Pipe bundles, fencing, poles |
| 1,200 mm / 48″ | 12.7 mm | 250 lbs / 114 kg | ~365 mm / 14″ | Industrial and logistics strapping |
For loads at the top of this table, see our heavy duty cable ties range; for the smallest sizes, miniature 2.5 mm ties are covered on the nylon cable ties page.
How to measure your bundle and pick the length
Work from the bundle, not from the shelf:
- Measure the bundle circumference. Wrap a strip of paper or string around the bundle and measure it flat. (Circumference ÷ 3.14 = diameter, if you need the diameter figure.)
- Add the working margin. The tie needs enough tail past the head to grip and pull — add roughly 25–30% to the circumference, or at least 50 mm.
- Round up to the next standard length. A bundle with a 250 mm circumference needs ~320 mm of tie, so choose a 380 mm size rather than stretching a 300 mm one to its limit.
Reverse lookup, if you already know the bundle diameter:
| Your bundle diameter | Minimum tie length |
|---|---|
| up to 20 mm (0.8″) | 100 mm / 4″ |
| 20–35 mm (1.4″) | 150 mm / 6″ |
| 35–50 mm (2″) | 200 mm / 8″ |
| 50–80 mm (3.1″) | 300 mm / 12″ |
| 80–125 mm (5″) | 450 mm / 18″ |
| 125–220 mm (8.7″) | 760 mm / 30″ |
| over 220 mm | 1,030–1,200 mm |
Matching width and tensile strength to the load
Length gets the tie around the bundle; width is what keeps it there. Match the tensile rating to the real mechanical load — the weight of the bundle plus vibration, wind, or handling stress:
- 2.5–3.6 mm (18–40 lbs) — static indoor bundles: signal cables, electronics, dressing wire runs.
- 4.8 mm (50 lbs) — the general-purpose width: power cables, automotive looms, garden and workshop jobs.
- 7.6–9.0 mm (120–175 lbs) — heavy cables, conduit, anything under vibration or outdoor load.
- 12.7 mm (250 lbs) — industrial strapping, pipes, poles, logistics.
Tensile ratings are minimum loop values under the UL 62275 test method (UL 62275 standard) — a tie rated 50 lbs holds at least that in a straight pull. For sustained loads, engineers commonly size with a 2:1 safety margin, and how much a tie really holds also depends on temperature and installation — we cover that in detail in how much weight a zip tie can hold.
Sizes by material: nylon, stainless steel, and specialty ties
| Material | Common size range | Typical tensile | Where it belongs |
|---|---|---|---|
| Nylon 66 (standard) | 80–1,200 mm, 2.5–12.7 mm wide | 18–250 lbs | Indoor and general use, approx. −40 °C to +85 °C |
| UV-stabilized nylon (black) | same as standard | same as standard | Outdoor and sunlight exposure |
| Stainless steel (304/316) | 150–1,200 mm, 4.6–12 mm wide | 200 lbs+ | High heat, chemicals, marine, fire-rated runs |
| Releasable nylon | 150–600 mm | up to ~120 lbs | Temporary bundling, re-usable fastening |
The same size behaves differently in different materials: a 4.6 mm stainless steel cable tie out-pulls a 7.6 mm nylon one and shrugs off temperatures that soften nylon. If your application runs hot, cold, wet, or in sunlight, choose the material first and the size second.
Mounting base sizes
Adhesive and screw-mount bases anchor ties to a surface, and the base must match the strap width: the slot in a 19×19 mm base takes straps up to ~4.8 mm; 28×28 mm bases suit 4.8–7.6 mm straps; 38×38 mm and larger take heavy-duty widths. A strap forced into an undersized slot, or rattling loose in an oversized one, is the most common reason mounted runs come away from the wall.
The sizing mistakes that make cable ties fail
- Sizing by length alone. A long, narrow tie closes around a heavy bundle — and then snaps under its weight. Check width and tensile rating, not just reach.
- Running at the limit. A tie stretched to its last locking teeth, or loaded at exactly its rated strength, has no margin. Round the length up and keep a 2:1 load margin.
- Ignoring the environment. Standard indoor nylon turns brittle in sunlight within months. Outdoors, use UV-stabilized black ties in the same size.
- Over-tightening. Cinching a tie as hard as possible bites into cable insulation and pre-stresses the strap. Tight enough that the bundle can’t slide is tight enough.
- Joining ties end-to-end for big bundles. Two linked 300 mm ties have a joint at head strength, not strap strength. For large bundles, use one tie of the correct length.
Buying cable tie sizes in bulk: what to check
Ordering at pallet scale rather than pack scale changes what matters. From our side of the factory, the checks that save buyers trouble are:
- Confirm size by all four numbers, not by name — “8-inch tie” doesn’t fix the width or tensile class. A purchase order that states 200 mm × 4.8 mm, 50 lbs avoids the most common supply mistake in this industry.
- Ask for the datasheet and certificates for the specific size, not the brand — certifications are issued per product line. Our test reports and certificates are on the certifications page.
- Match packaging to the size. Small sizes ship 100/bag; long heavy-duty sizes come in lower counts and different carton dimensions, which changes your freight volume. MOQ and packing options depend on the size and color — confirm with our team when you request a quote.
FAQs on cable tie sizes
What is the most common cable tie size?
The 100 mm (4″), 150 mm (6″), 200 mm (8″) and 300 mm (12″) sizes in 2.5–4.8 mm widths cover most everyday work. The 300 mm × 4.8 mm tie is the single most versatile size: long enough for an 85 mm bundle, strong enough at 50 lbs for most static loads.
How do I know what size cable tie I need?
Wrap a string around your bundle and measure it, add about 25–30%, and round up to the next standard length. Then check the tensile rating against the load: 18–40 lbs for light indoor cables, 50 lbs for general use, 120 lbs+ for heavy or vibrating bundles.
What do the two numbers in a cable tie size mean?
A size like 300 × 4.8 mm is length × width. Length determines the maximum bundle diameter; width determines the tensile strength class.
What sizes do heavy duty cable ties come in?
Heavy duty generally means 7.6 mm width and up. Common sizes run 300–760 mm long at 7.6–9.0 mm (120–175 lbs), and extra heavy duty reaches 1,200 mm at 12.7 mm width (250 lbs).
Are cable tie sizes metric or imperial?
Both systems describe the same ties: 100 mm = 4″, 200 mm = 8″, 300 mm = 12″. Metric is standard in manufacturing and export paperwork; imperial dominates North American retail. The chart above lists every size in both.
Get the exact sizes you need, factory direct
We manufacture the full size range in this guide — standard, UV-stabilized, releasable and stainless steel — in any color, with size-specific test data available on request. If you’re specifying sizes for a bulk order, send us the bundle diameters and load conditions and we’ll confirm the right size and packing: request a bulk quote.
By the Shangbo Technical Team · Last updated: 25 August 2026
