A tablecloth can be wide enough to cover the tabletop and still look surprisingly short once it is in place. The missing measurement is the drop: the distance the fabric hangs beyond the edge.
Choose that distance deliberately before shopping. A casual everyday table, a formal setting and a table used by children may need different practical arrangements.
Measure the table in the configuration you will use
Include extension leaves if they will be fitted. Record the actual length and width, or the diameter for a circular table. Do not rely only on how many people the furniture is advertised to seat.
For a rectangular table with the same intended drop on every side, add twice the drop to both the table length and width. For a round table with a round cloth, add twice the drop to the diameter.
As an illustrative calculation, a table measuring 140 by 80 centimetres with a 20-centimetre drop on each side calls for a finished cloth approximately 180 by 120 centimetres. The arithmetic describes the intended dimensions; product tolerances and fabric behaviour still need checking.
Look at the corners and chairs
A rectangular cloth’s corners can hang differently from its straight sides. Test the effect with a clean sheet or sample if the arrangement is unfamiliar. Check chair arms, table legs and the space people need to sit and stand.
A very long drop may be unsuitable where fabric can be pulled, caught or stepped on. Consider the people using the table and keep hot dishes and other hazards in mind when choosing the setup.
Buy for the finished result
Read whether the listed dimensions describe the finished product and check the care instructions. Ask the supplier about expected dimensional changes if relevant; do not add an arbitrary shrinkage allowance to every fabric.
If making the cloth, distinguish finished size from cutting size. Hem allowances belong in the construction calculation, not in the visible drop you chose at the table.
Keep your measurement note with a quick sketch showing the desired overhang. That makes it easier to compare products without repeatedly measuring the furniture.
A tablecloth fits well when its dimensions support the way the table is used. The label “six-seater” is a starting clue, but a measured tabletop and a chosen drop give you a much clearer answer.