Hidden door hinges
Updated: 23 October 2026
Hidden door hinges are what you want when the door should show no knuckle: a bookcase that is really a doorway, a flush leaf, or a small folding flap. A 35 mm kitchen cup will not do that, and a fire-rated bullet is not a fire-door hinge. This page stays with the mortise and cross hinges in the set, and it stops if the door has to resist fire. Nothing on this page is a 35 mm Forstner sequence. Prices are on the [concealed hinges comparison](/hub/diy-supplies/concealed-hinges). A qualifying purchase can earn us a commission at no extra cost to you.
Hidden door hinges are what you want when the door should show no knuckle: a bookcase that is really a doorway, a flush leaf, or a small folding flap.
Hidden door hinges are what you want when the door should show no knuckle: a bookcase that is really a doorway, a flush leaf, or a small folding flap. A 35 mm kitchen cup will not do that, and a fire-rated bullet is not a fire-door hinge. This page stays with the mortise and cross hinges in the set, and it stops if the door has to resist fire. Nothing on this page is a 35 mm Forstner sequence. Prices are on the concealed hinges comparison. A qualifying purchase can earn us a commission at no extra cost to you.
Our top picks
| Badge | Product | Type | Opening | Load stated | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Heuskay Heuskay 2-pack 45 mm cross hinge | Cross hinge | 180° | n/a | 4.9 | about £9.99 | View offer |
| Alternative |  TVOOD TVOOD 180° hidden door hinge | Invisible mortise | 180° | 40 kg with two hinges | 4.4 | about £24.92 | View offer |
| Alternative |  VigilLox VigilLox 2-pack 110° mortise | Invisible mortise | 110° | 50 kg attribute; 110 lb per pair in the bullet | 3.1 | about £19.54 | View offer |
On this page
Which hidden hinge is in the basket
Three sizes share the word concealed. The passage-door shape here is a 180° mortise hinge: TVOOD at £24.92 and JIODEKEYI at £23.48, both stating 40 kg and 3-way adjustment in millimetres. TVOOD’s title says a 2-pack and the unit-count field is 1.0. JIODEKEYI’s unit count is 1.0. WMLBK is a black 180° cross hinge at £23.46 for two, with a load field of 176 lb. VigilLox is the thick-door pair at £19.54, 110°, for a leaf at least 40 mm thick. Heuskay is the small one: two 180° cross hinges at £9.99 for a flap. The bullet says 13 × 45 mm, the dimensions field says 45 × 45 mm, and the title says 45 mm. Confirm the pack count on the live page, because a title that says two and a unit count of 1.0 may be one hinge.
Thickness, recess and load
VigilLox is the only listing here that states a minimum thickness: at least 40 mm, with a recess of about 13 mm. The bullet caps leaf width at 1000 mm and names hidden bookcase doors. The attribute load says 50 kg. The bullet says 110 lb per pair. Both stay, and they are not a checked conversion of each other. amazon.co.uk shows 3.5 from seven ratings. Play developed in the pin of the top hinge, one door was not flush when closed, and one pair was returned. TVOOD states 40 kg when two hinges are used. If the unit count of 1.0 is what arrives, one hinge is not that 40 kg line. WMLBK’s load field is 176 lb, left in pounds. If your leaf is under 40 mm, VigilLox’s own line says it is too thin.
Fitting is a mortise
These hinges sit in a slot in the door edge and the frame. That is a router or a joiner, not a Forstner bit in the back of a chipboard door. VigilLox says drilling and slotting are required, recommends a professional if the mortise is unfamiliar, and suggests a test notch on scrap. Screw count is 10 in one row and 20 in the bullet. A UK review of the Heuskay pair says no template was included and a router is needed. WMLBK reviews include a hinge that snapped while it was being fastened, and instructions that were missing or in Chinese. Do the scrap notch before the real edge.
Fire doors are a different product
If the door is a fire door, stop. Nothing in this set shows BS EN 1935, or a fire test of the door assembly to EN 1634-1 or EN 1634-2. TVOOD uses smoke-proof as a marketing word. JIODEKEYI says suitable for fire-rated doors and gives no standard, no report and no melting point. A fire-rated adjective is not a certificate. GOV.UK’s guidance under the Fire Safety (England) Regulations 2022 expects a self-closer that shuts the door from fully open and from about 15°. Certifire CF 5810, behind hinges such as Simonswerk TECTUS FR, is a different product. That certificate does not list these ASINs. Leave FD30 doors to hinges that carry the test.
Common questions
Are hidden door hinges the same as 35 mm cabinet hinges?
No. A 35 mm cup is bored into the back of a cupboard door. The hinges here sit in a mortise in the edge, or in a small cross pocket for a flap. TVOOD, JIODEKEYI, WMLBK and VigilLox are door hardware. Heuskay is a small furniture cross hinge. None of them replaces a full-overlay kitchen cup.
How thick does the door need to be for the VigilLox pair?
At least 40 mm, with a recess of about 13 mm. The bullet also limits leaf width to 1000 mm and mentions hidden bookcase doors. An 18 mm kitchen door is below that line. The listing suggests a professional if you have not cut this mortise, and a test notch on scrap first.
What load figures are actually printed, and where do they conflict?
TVOOD states 40 kg with two hinges, while the unit count may be one. JIODEKEYI states 40 kg on a unit count of 1.0. WMLBK’s attribute says 176 lb, which this page does not convert. VigilLox says 50 kg in the attribute and 110 lb per pair in the bullet. Keep both VigilLox figures. They are not shown as checked equivalents.
Do I need a router or a joiner?
A mortise means a router or a joiner, not a cupboard Forstner bit. VigilLox says so. A Heuskay UK review says there is no template and a router is required. WMLBK reviews include missing or Chinese instructions and a hinge that snapped while it was being fastened. Cut scrap first. For a full-height leaf, hire the joiner.
What should a fire door use instead?
Certified ironmongery with a stated fire test, not one of these ASINs. The contrast is a hinge such as Simonswerk TECTUS FR on Certifire CF 5810, with three hinges on an FD30 door in Allgood’s description and a minimum leaf around 44 mm in the certificate text for the 30-minute timber case. GOV.UK also expects a real self-closer. This set does not supply that.
Related pages
Sources
Public UK sources and the amazon.co.uk listings compared on this page. Prices captured 19 October 2026. Updated 22.10.2026.
- GOV.UK: General Product Safety Regulations 2005 (retrieved October 2026)
- Consumer Rights Act 2015, goods (retrieved October 2026)
- NBS: BS EN 15570:2008 (retrieved October 2026)
- GOV.UK: Fire door guidance (retrieved October 2026)
- Code of Practice: hardware for fire and escape doors (retrieved October 2026)
- Häfele UK: cabinet hinge FAQs (retrieved October 2026)
- DIY Doctor: fit a concealed hinge (retrieved October 2026)
- Blum UK: CLIP top BLUMOTION (retrieved October 2026)