The juxtaposition of the sabil-kuttab, bent entrance, prayer hall, and mausoleum created two sets of protrusions. The first, consisting of the sabil-kuttab and the bent entrance, follow the street's alignment; the second, following the prayer hall and the mausoleum, is oriented towards Mecca. The two sets of protrusions, combined with the square-octagonal-cylindrical minaret and the dome with an elaborate exterior zone of transition made up of half prisms, present an unusual volumetric composition with contrasting forms counterbalancing each other.

Its dome, with its triangular shoulders, is covered with a repetitive arabesque pattern of interlacing leaves and hearts. This is a two-layered, tapestry-like carving which appears as a simplified version of the intricate theme introduced on the tome over the mausoleum of Sultan Qaytbay.  The two layers on Qaytbay's dome are distinguished from one another a geometrical pattern and an undulating arabesque pattern that produces a contrasting surface articulation. This dynamic equilibrium between the two patterns is further accentuated by a difference in planes. The two interlacing, uniplanar arabesque layers on the dome of Khayrbak exhibit similar contrasting surface articulation. 

The minaret has a geometric star-shaped stucco design carved on the brick shaft. The threshold of the minaret is made from a block of stone taken from a pharaonic building. It includes hieroglyphic inscriptions, including a depiction of the mummified Osiris. Unfortunately, its original top is lost to us, but old illustrations depict it as the usual pavilion type.

The minaret from an earlier photo showing its top, and later without

Under the dome on the south side, the wall is on an angle, and on the western or street side, the wall is adjusted to conform to the street alignment between the mausoleum and the ruins of the palace.  On the eastern side of the dome there is an arch that includes an interior staircase that connects the palace with the mausoleum. This was the palace built by Amir Alin Aq in the late thirteenth century AD and was afterwards inhabited by various amirs, including Khayrbak. 

Arched windows in pairs adorn the face of the mausoleum. They are surmounted by circular windows, while the lower windows are rectangular. Other decorations include carved stone panels and joggled lintels. 

The marble, inlaid portal, which leads through a corridor into a courtyard, is of the trilobed groin-vaulted variety. To the left side of the portal  passage is a sabil-kuttab, which protrudes slightly and balances the protrusion under the minaret at the other end of the facade. The entrance tot he sabil-kuttab through a door on the left side of the entrance corridor. The mosque is approached from the courtyard, which is uncommon. There is a courtyard on the east side of the mosque that contains a tomb and is bordered by Salah al-Din's (Saladin) eastern city wall, separating it from the cemetery of Bab al-Wazir. 

The interior of the mosque is a hall consisting of three cross vaults supported by pointed arches. The central vault has an octagonal opening to admit illumination. On the eastern wall is the prayer niche, which is paneled like the rest of the wall with a polychrome marble dada and a conch of plain stone. A rather awkward feature here are the windows above the prayer niche, which are partly hidden by the curve of the central arch supporting the vault. It seems as though the architect might have begun the walls with the intention of roofing them as usual with a wooden ceiling, but then altered the plan after the qibla wall was erected and instead added arches for the vault. 

Two Views of the Interior of the prayer hall

It is possible that a shortage of wood might explain this odd feature. Egypt has always had to import wood, and in the time of Sultan al-Ghuri, it would have been imported from Anatolia. Since Egypt was already involved in the disturbances caused by the Ottoman conquests, timber may have been difficult to obtain. 

Plan of the Complex of Khayrbak

The dikka, which is a loggia made of wood, is situated on the western wall opposite the prayer niche. This wall, which includes recesses, is adjusted to the street alignment by irregular thickness in the wall. Here, the qibla wall is not properly oriented to Mecca, as is the prayer niche in the mausoleum. This is most likely due to a lack of space, which raises the question of whether the space occupied by the mosque was originally planned for another purpose and later adapted as a religious building.

A decorative pattern within the mosque

Facing the entrance of the Mosque at the back of the prayer hall is a trilobed portal with a groin vault adorned with ablaq masonry and stalactites in the two side arches that leads into the mausoleum. An interesting architectural element of this building is the treatment of the mausoleum entrance, which is enhanced by a portal and which has a pair of maksalas. While this treatment is common on facades, it is not usually found in interiors. 

The mausoleum walls are not straight, and inside they show irregularities in the arrangement of the windows. Here, the inner window openings do not correspond to the outer openings, so that the openings run obliquely through the thickness of the masonry. 

Interestingly, the mausoleum is dated to 1502/3 AD, but the foundation deed of the madrasa has a much later date of 1521. There are no dated inscriptions on the madrasa, but there is also no break in the masonry of the mausoleum and madrasa to suggest that they were constructed at different times.

The madrasa's foundation deed indicates that it was planned for ten students who were also Sufis. Five living units under the floor of the mosque, reached from the yard, provided their lodging. 

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