The short answer
Count the separate runs in your display and buy that many reels. Then check your longest run against the published per-reel capacity: 60 feet on the Zober four-reel bag, 80 on the three-reel one. A 100-foot strand does not fit either, and that is the check most people skip.
Typical runs, and what each needs
Common parts of a display, their typical lengths, and the reel each needs| Run | Typical length | Bulbs | Reel needed |
|---|
| Indoor tree, 6 to 7.5 ft | 50-100 ft | 200-400 mini | One 60 ft reel per strand |
| Indoor tree, 9 ft | 100-150 ft | 400-600 mini | One 80 ft reel per strand |
| Mantel or bannister | 20-35 ft | 100-150 mini | Shares a 60 ft reel |
| Single window | 15-20 ft | 50-100 mini | One cord wrap |
| Porch rail | 35-50 ft | 150-200 mini | One 60 ft reel |
| Roofline, single story | 100-200 ft | 50-100 C9 | Two or three 80 ft reels |
| Shrubs and bushes | 25-50 ft each | Net or mini | One reel per net |
These are typical ranges from how these products are sold, not measurements of your house. Use them to plan; use your own count to buy.
The five-minute count
- 1
Walk the display and list the runs
One line per separate strand. Tree, mantel, each window, stair rail, porch, roofline, shrubs. Do it while the lights are still up, so you do not forget the one behind the sofa.
- 2
Write the length beside each
From the box if you kept it, from the tag on the plug, or from the bulb count. One hundred mini bulbs at four inches apart is roughly 33 feet of lit length, plus the lead.
- 3
Count the lines
That number is your reel count. It is not related to total footage, and buying on total footage is the mistake this page exists to prevent.
- 4
Check your longest run
Against the published per-reel figure, not the total. If your longest strand is 100 feet and the reels are 60, you have a problem no amount of total capacity solves.
Published per-reel capacities
What each product publishes per reel| Product | Reels | Per reel | Total |
|---|
| Zober 3-reel bag | 3, metal | 80 ft | 240 ft |
| Zober 4-reel bag | 4, plastic | 60 ft | 240 ft |
| Sterilite light and garland box | 4, removable | Up to 400 lights | Not stated in feet |
| HOMZ organizer pair | 8 cord wraps | Not published | Not published |
Note the unit change. Zober publishes feet; Sterilite publishes bulb count. If your strands are described in bulbs, Sterilite's figure is directly usable. If they are described in feet, Zober's is. Converting between them means knowing your bulb spacing, which is on the box: four inches is common for minis, eight to twelve for C7 and C9.
Bulb type changes the arithmetic
A published capacity of 400 lights per reel assumes mini bulbs, which are small and sit close to the wire. C9 bulbs are considerably larger, and a strand of them takes up far more space per foot on a reel.
As a rule of thumb, if your outdoor strands are C7 or C9, assume a reel holds around half the length its mini-light figure suggests, and check when you wind the first one. That is not a published number and we are not presenting it as one — it is the arithmetic of bulb diameter against reel depth.
Leave room
Displays grow. Buy one more reel than your count, or buy a format that publishes more reels than you currently need. A spare reel costs very little; adding a strand next year with nowhere to put it means it goes in loose, and one loose strand in a container of reels is enough to reintroduce the tangle.
Once the reels are wound, they need somewhere to live. That is a bin question rather than a light question — see bins by capacity.