Comment calculer les dimensions d'un abat-jour pour une lampe ?

Prenez la hauteur totale, du bas du pied au haut de la douille : l'abat-jour en occupe environ le tiers. Pour le diamètre du bas, comptez deux fois la largeur du pied à son point le plus large. Le diamètre du haut, lui, se cale sur la douille, pas sur le pied.

Quel abat-jour pour quel pied de lampe ?

Le pied commande la forme avant la couleur. Une base large et ronde supporte un abat-jour large et court, une tige fine appelle un format plus haut et plus ouvert. Sur un relevé de 31 références de notre collection au 30 septembre 2026, la forme ronde ressort sur 58 % du relevé, la tube sur 16 %, la goutte sur 10 %.

Quel est le système pour fixer un abat-jour ?

Trois systèmes couvrent la quasi-totalité des lampes : l'araignée, la douille à bague et la patère. On les distingue en retournant l'abat-jour, où l'on voit soit des bras métalliques, soit un anneau fileté, soit une tige unique.

Quelle est la hauteur standard d'une lampe sur pied ?

La plupart des lampadaires de salon culminent entre 150 et 180 cm du sol, les modèles liseuse entre 140 et 160 cm. Le chiffre qui compte est celui de l'assise : une fois assis, le bas de l'abat-jour doit rester au-dessus de la ligne du regard.

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Lampshade size: the right proportion with the lamp base

This article is also available in French: Taille abat jour par rapport au pied de lampe

26/09/2026 · 9 min read · By the Designix team

Take three measurements on your lampshade: the bottom diameter, the top diameter and the height. The bottom should extend about 5 cm beyond the socket on each side, and the height should stay close to one third of the base height. These three measurements are enough to decide.

How do you calculate the dimensions of a lampshade for a lamp?

Take the total height, from the bottom of the base to the top of the socket: the lampshade takes up about one third of it. For the bottom diameter, count twice the width of the base at its widest point. The top diameter, for its part, matches the socket, not the base.

Which lampshade shape for which lamp base

	Round lampshade	Tube lampshade	Teardrop lampshade
Share of the survey (31 refs., 30/09/2026)	58 %	16 %	10 %
Base it suits	ball base, wide column, bedside base	slender base, metal stem, narrow column	crystal base, glass base, small base
Effect on light	wide, diffuse halo, lights the room	narrow beam, lights a surface	contained, downward light
Height to aim for	about one third of the total height, base included	one third of the total height, never less	one third, without ever hiding the socket
Dominant material in the survey	linen and fabric	metal	glass
Bulb base on the listed products	E27	E27	E27

Lampshade size in relation to the lamp base

Our collection of lampshades for table lamps has 789 references as of 30 September 2026: you are not facing a binary choice. The bottom diameter is read on the base, never on the stem, and a base that flares out calls for a wider lampshade than a straight base of the same height.

Base shape	Bottom diameter	Lampshade height
Round or ball	1.5 to 2 times the base diameter	about one third of the total height
Stem, column, slender base	2.5 to 3 times the base diameter	one third to one half
Floor lamp	1.5 to 2 times the base	one quarter to one third

Beyond 45 cm, you no longer simply place the lampshade, you install it: a lampshade 50 cm in diameter belongs to large spaces, hallway or living room.

Lampshade size in relation to the lamp

A lampshade narrower than the body of the lamp leaves the bulb in the field of view. The complete silhouette must fit into a regular cone, wide at the bottom and clean at the top.

Bottom diameter: at least one third more than the widest point of the base
Top diameter: at least the width of the socket
Height: one third of the lamp, from the base to the top of the socket
Overhang: the top of the lampshade covers the bulb without touching it

What the third does not say: the socket and the seated eye

The socket decides more than the rule. In a survey of 31 references from our lampshade collection as of 30 September 2026, the E27 base is declared on 97 % of the listed products. Your lampshade will therefore almost always take a wide screw bulb.

E27 base bulbs cover this need, including the filament version, whose warm tint forgives a thick fabric.

The second decision, the one no rule measures: the height of the bottom of the lampshade. Seated on the sofa, it must fall above the line of sight, otherwise the bulb dazzles. A bulb wattage for a living room that is too high is hard to compensate for behind a thin fabric.

If you prefer to validate your measurements before ordering, you can ask for advice on a proportion: give us your three measurements, and we will reply on the shape to choose.

Which lampshade for which lamp base?

The base dictates the shape before the colour. A wide, round base supports a wide, short lampshade, a slender stem calls for a taller and more open format. In a survey of 31 references from our collection as of 30 September 2026, the round shape stands out on 58 % of the survey, the tube on 16 %, the teardrop on 10 %.

Lampshades to proportion with your lamp base

See the whole selection: Lampshades: Pendant, Table Lamp and Floor Lamp

Lampshade and round or ball base

A ball accepts a lampshade wider than itself, provided the bottom stays open: the light runs towards the floor and lights the base instead of crushing it. This is the case with the frosted glass balls fitted to many bedside lamps.

The slightest discrepancy shows to the naked eye. An lampshade for a round base is chosen by keeping the ball entirely visible, never half swallowed by the fabric.

Lampshade and slender base, stem or column

A slender stem supports a tall, wide lampshade without looking heavy: the contrast between the thin line and the fabric creates the character. This is the case with large table lamps, where the lampshade often exceeds 35 cm in diameter and forms half of the silhouette.

On a wide body, surface is needed: a large lampshade avoids the mushroom effect.

Lampshade and floor lamp

On a floor lamp, the lampshade is seen from a distance: it is the only part of the light whose size is perceived from the sofa. A format that is too small makes a mushroom, a format that is too large crushes the room.

Diameter: close to that of the base
Bottom of the lampshade: above the line of sight, once seated
Material: linen or fabric for ambient light, glass for a sharper sparkle

What system is used to fix a lampshade?

Three systems cover almost all lamps: the spider, the ring socket and the patere. You tell them apart by turning the lampshade over, where you see either metal arms, a threaded ring, or a single stem.

Socket, spider, patere: how to recognise yours

Spider: two or three metal arms in the centre of the opening, on which the lampshade rests
Ring socket: a threaded ring around the socket, onto which the lampshade is screwed
Patere: a central stem under the socket, tightened with a wing nut
Clip: two blades that clip onto the bulb, reserved for small formats

The top diameter of the lampshade must match the system in place: a spider that is too wide lets light through the top, a ring that is too tight will not screw on.

How to put a lampshade on a lamp base

With the lamp switched off and the bulb removed, the operation takes a few minutes and requires no tools.

Cut the power before removing the old lampshade
Remove the bulb so as not to force the socket
Present the lampshade flat before tightening
Tighten by hand, never with pliers, on a ceramic or metal socket

The details of assembly depend on the system, and the complete method to install a lampshade comes down to one check: the bottom must stay parallel to the floor.

Which lamp base are you going to dress?

What is the standard height of a floor lamp?

Most living room floor lamps peak between 150 and 180 cm from the floor, reading models between 140 and 160 cm. The figure that matters is that of the seat: once seated, the bottom of the lampshade must stay above the line of sight.

Lampshade size on a floor lamp

On a tall body, the lampshade takes up one quarter to one third of the total height, often 35 to 45 cm in diameter. An assembled model gives the scale better than a tape measure: our selection of floor lamps lets you compare several proportions at a single glance.

Tall base: raise the lampshade rather than shrink it

A tall body does not call for a smaller lampshade, but for a lampshade placed higher. Reducing the diameter darkens the room and brings the bulb back into the field of view.

Extended stem: the most discreet correction
Raised socket: when the stem is fixed
Taller lampshade: preferable to a narrower lampshade

The measurements to aim for depending on the room are detailed in our guide to floor lamp height.

Once the proportion is right, the atmosphere remains: linen diffuses a warm light in the living room, glass lets through a sharper sparkle.

This second character can be seen in our choice of glass light fittings, useful when the lampshade mainly serves to reveal a material.

To judge a fabric in person, our Designix Google listing lets you find the address of the workshop in Vaulx-en-Velin.

Frequently asked questions about lampshade size

How do you calculate the dimensions of a lampshade for a lamp?

Take three measurements: bottom diameter, lampshade height and total lamp height. The lampshade takes up about one third of the total height, and its bottom diameter exceeds that of the base. The socket must stay hidden under the top edge.

Which lampshade for which lamp base?

A ball base or a wide column calls for a round lampshade, whose bottom diameter clearly overhangs. A slender base or a metal stem supports a tube lampshade, which is narrower. On a turned crystal or glass base, a teardrop shape remains the most accurate.

How do you choose the size of your lampshade?

Start with the desired total height, then work down: one third of that height gives the lampshade height. Then check that the bottom edge does not fall below your line of sight when you are seated.

How do you put a lampshade on a lamp base?

It all depends on the fitting. A ring screws directly onto the socket, a spider rests on its circle with three arms, a patere clips onto the frame of the base. Identify the system before buying, as it determines compatibility.

What system is used to fix a lampshade?

Three fittings coexist: the ring socket, the simplest to change; the spider, which rests on a socket or a dedicated support; the patere, reserved for lampshades on a frame. The E27 base, present on almost all of our listed products, remains the reference.