How to tape a carton so it arrives sealed, and how much tape it takes

A carton rarely opens in the middle of its seam. It opens at the ends, where one strip of tape stops at the edge of the flap and the board starts to lift.

So here is the short answer. Tape the bottom of the carton first, before you fill it. Use the H pattern: one strip along the centre seam and one across each end. Let every strip run about 5 to 7 cm down the sides, and rub it down with your palm. For cartons above about 15 kg, use 3 inch tape.

A normal shoebox-size carton takes about 2 m of tape done this way.

We make packing tape at our plant in Jaipur. This is the method we would teach any new packer, and we explain it below with the maths.

Is one strip enough, or do you need the H-tape method?

One strip along the top seam and one along the bottom is enough for a light box of clothes. It is not enough for anything heavy, fragile or full to the brim.

The H pattern adds two short strips across the ends of the seam on each face. Seen from above, the three strips look like the letter H. Those two extra strips hold the corners of the flaps, which is exactly where a single strip lets go.

The couriers say the same. Delhivery's packaging guidelines ask sellers to seal the centre seam of the top and bottom with pressure-sensitive tape such as BOPP, and to use H-taping on the centre and edge seams for heavier fragile items. You can read Delhivery's packaging guidelines on their help centre.

My own rule is simple. If the packed carton is above 2 kg, or anything inside can break, it gets the H on both faces.

How do you H-tape a carton, step by step?

Fold the bottom flaps shut and turn the empty carton upside down.
Run one strip along the centre seam. Start about 6 cm down one end wall and finish about 6 cm down the other.
Run one strip across each end of the seam, at right angles to the first, again with about 6 cm down each side wall.
Rub every strip down with your palm, end to end. Pressure is what makes this kind of tape stick.
Turn the carton over and pack it. Wrap the product, fill the gaps, close the flaps and shake it. If anything moves, add fill. Our guide on packing fragile orders without plastic covers this part in detail.
Tape the top the same way: centre strip first, then the two end strips.
Stick the shipping label on the top face, flat, and keep tape off the barcode.

India Post's Parcel Packaging Standards (Parcel Directorate, 2022) also say tape should not overlap address labels or bar codes. A wrinkle of tape over a barcode can make it hard to scan.

Why tape the bottom first?

Because the bottom carries the load, and you cannot tape it properly once the box is full.

Turn a packed carton over to tape its base and the product shifts. You also cannot press the tape against flaps that are hanging under weight. Seal the empty box while it sits upside down on a flat table, press the strips hard, and then fill it. It takes no extra tape, only a different order.

Hands pressing clear tape down along the top seam of a brown carton with a red tape dispenser — Photo: Tima Miroshnichenko on Pexels

How far should the tape run down the sides?

About 5 to 7 cm, i.e. 2 to 3 inches, on every end of every strip.

Less than that, and the end of the strip sits on the edge of the flap where the board bends. That spot moves every time the carton is lifted, and the tape peels from there. Much more than that, and you are only using up the roll. I use 6 cm for all the maths below.

When do you need 3 inch tape?

Use 3 inch tape when one 2 inch strip cannot cover the flap gap comfortably, or when the carton is heavy enough that the flaps push hard against the tape.

Here is the table I would start from. Treat the weights as a starting point and test one packed carton of your own before a full dispatch. The carton grades come from the couriers' own guidance: Delhivery suggests 5 ply cartons for products that are above 4 kg and fragile, and India Post's standards move from single wall to double wall boxes at the 15 kg size.

Packed weight	Carton	Tape width	Pattern
Up to 2 kg, soft goods	3 ply	2 inch	One strip top and bottom is usually fine
2 to 5 kg	3 ply, or 5 ply if fragile	2 inch	H-tape, top and bottom
5 to 15 kg	5 ply	2 inch, or 3 inch on the centre seam	H-tape, top and bottom
15 to 25 kg	Double wall	3 inch	H-tape, plus a second strip on the bottom centre seam
Above 25 kg	Double wall	3 inch	H-tape, and ask your courier about strapping

Tape cannot rescue a weak box. If the carton walls bulge or the flaps do not meet, change the box first.

I say this as a tape maker. We would happily sell you more tape, but I would rather you spend that money on a better carton.

We sell 3 inch brown tape in 65 m rolls for sellers who need it now and then, and 300 m rolls for packing tables that use it all day. You will find both in our brown tapes. A 3 inch roll needs a 3 inch dispenser, so check yours first.

How much tape does one carton take?

Here is the maths, so you can check it with your own carton. I have kept it simple on purpose, so anyone at your packing table can redo it. The carton's height does not matter here. Only the length and width of the flaps do.

Centre strip = carton length + 12 cm (6 cm down each end).
Each end strip = carton width + 12 cm.
One face with the H = centre strip + 2 end strips.
Both faces = twice that.

For a 30 x 20 x 15 cm carton: the centre strip is 42 cm, each end strip is 32 cm, one face takes 106 cm, and both faces take 2.12 m.

Carton (L x W x H, cm)	One strip, top and bottom	Full H, top and bottom	Cartons per 65 m roll, full H
20 x 15 x 10	0.64 m	1.72 m	about 37
25 x 20 x 10	0.74 m	2.02 m	about 32
30 x 20 x 15	0.84 m	2.12 m	about 30
35 x 25 x 20	0.94 m	2.42 m	about 26
45 x 35 x 30	1.14 m	3.02 m	about 21

These are approximate, and they assume no waste. In real packing, take off about 10% for bad cuts, folded strips and the last turn on the core. So a seller shipping 300 cartons a month of the 30 x 20 x 15 cm size needs roughly 300 x 2.12 m = 636 m, plus waste, about 700 m. That is around 11 rolls of 65 m, or a little over two 300 m rolls.

If you are choosing between clear tape widths and roll lengths, our guide to which clear tape to buy has the full comparison.

Why does packing tape fail?

When a seller tells us a carton opened on the way, the cause is almost always one of these five. Only after them would I blame the tape.

Dust. The glue holds the dust, and the dust holds nothing. Wipe dusty or recycled board with a dry cloth before you tape.
Cold. In a north Indian winter, a godown at 7 in the morning is cold, and cold glue is stiff. It cannot flow into the board. Keep rolls indoors at room temperature and press harder in winter.
Over-stretching. If you pull the tape tight like a rope, the film stretches. Then it tries to shrink back, like a rubber band, and pulls its own ends up. Let the tape lie on the box.
No pressure. This tape sticks with pressure, not with time. A strip that was only laid on, never rubbed, is half stuck.
The box. Overfilled flaps bulge and push the tape off. Underfilled cartons collapse and tear it.

When it really is the tape, it is usually a thin glue coat or a short roll. We make BOPP tape at our own plant in Jaipur, and this short video shows the line.

How BOPP packing tape is made at the JPPL plant in Jaipur (video) — Video: How BOPP packing tape is made at the JPPL plant in Jaipur (our YouTube channel)

How should you handle a returned or resealed carton?

Returns come back with old tape, old labels and a carton that has already done one trip. Be stricter with them, not softer.

Open every return on video, starting with the sealed carton and its label. If there is a dispute about what came back, that video is your record.
Cut along the seam, not through the flaps. A knife across a flap weakens it for the next trip.
Check the carton. Crushed corners, damp patches, torn flaps or a layer of old labels mean a new carton. A box that has done one trip is weaker than it looks.
If you reuse it, remove or fully cover every old shipping label and barcode. Two barcodes on one box can confuse the scanner and the person reading it.
Peel any old tape that is lifting. Never tape over a strip that has already let go, because your new tape is then only as good as the old one underneath it.
Re-tape with the full H, and run every new strip past the old tape onto clean board.

For a replacement going out to an unhappy customer, I would always use a fresh carton. It is the cheapest apology you can send.

Questions sellers ask about taping cartons

Can I use 1 inch tape on a carton if I run two strips side by side?

You can, but it is slower and it uses more tape. Two 1 inch strips leave a weak line down the middle. Buy 2 inch tape for cartons and keep 1 inch for envelopes and food boxes.

Is kraft paper tape strong enough for the H method?

For a normal ecommerce carton, yes. For a heavy or export carton, add a second strip across each seam and test one box first. The trade-offs are in kraft paper tape vs BOPP tape.

Should I tape around the whole carton?

No. A band of tape round the middle adds metres but does nothing for the flaps. The H holds the flaps, which is where cartons open. For really heavy boxes, strapping does a better job than more tape.

Not sure your tape suits your cartons? Our free packaging sample has brown tape and a brown carton. Tape one box with the H, leave it in your warmest corner for a day, and try to open it with your fingers. If you cannot, you are ready to ship.