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FACS-huijauslehti

A visual guide to the Facial Action Coding System (FACS) and beyond: every action unit (AU) with a reference GIF, the muscles involved, and notes, plus actions FACS leaves out (marked #notFACS).

All actions are performed by the author, FACS-certified with 14 years of experience in facial muscle isolation.

By Melinda Ozel Updated November 2026 How to cite

#notFACS marks actions I have identified and named that do not exist in FACS. FACS was built to identify facial behavior, so it lacks documentation for some finer movements. To fill the gaps, I define my own: lip cincher (vertical lip tightener), y-axis and z-axis dimpler, open-eyed blink, and more. These distinctions are especially useful for lipsync technology and photoreal characters.

All actions at a glance

All 43 actions in one table, in numerical order, with #notFACS actions at the end. Select an action to jump to its entry.

CodeActionMuscle(s)Region
AU1sisäinen otsan kohottajafrontalis, medialBrows & forehead
AU2ulompi otsan kohottajafrontalis, lateralBrows & forehead
AU4otsanlaskijacorrugator supercilii, depressor supercilii ja/tai procerus procerusBrows & forehead
AU5yläkannen korottajalevator palpebrae superioris (LPS)Silmät ja posket
AU6posken kohottajaorbicularis oculi, orbitalSilmät ja posket
AU7kannen kiristinorbicularis oculi, preseptal palpebralSilmät ja posket
AU8huulet toisiaan kohtiorbicularis orisHuulet
AU9nenä ryppyinenlevator labii superioris alaeque nasi (LLSAN)Nose & mid-face
AU10huulen kohottajalevator labii superioris (LLS)Nose & mid-face
AU11nasolabiaalisen uurteen syventäjäzygomaticus minorNose & mid-face
AU12huulten kulmavetolaitezygomaticus majorhuulien kulmat
AU13terävä huulivedinlevator anguli oris (LAO)huulien kulmat
AU14dimpler osittain #notFACSbuccinatorhuulien kulmat
AU15huulten kulman puristindepressor anguli oris (DAO)huulien kulmat
AU16alahuulen painajadepressor labii inferioris (DLI)Lower lip & chin
AU17leuan kohottajamentalisLower lip & chin
AU18huulten nyppyyntyminenincisivus labii inferioris & incisivus labii superiorishuulien kulmat
AD19kieli näyttääit dependsAction descriptors
AU20huulten venyttäjärisoriushuulien kulmat
AU21kaulan kiristinplatysmaMisc
AU22huulten suppiloitsijaorbicularis oris, peripheralHuulet
AU23huulten kiristinorbicularis oris, marginalHuulet
AU24huulten painajaorbicularis oris, marginalHuulet
AU25huulet avautuvatit dependsMisc
AU26leuan pudotusrelaxation of masseter, temporalis, medial pterygoidLeuka
AU27suun venytyslateral pterygoid + suprahyoidsLeuka
AU28huulet imevätorbicularis oris, marginal + peripheralHuulet
AD29jaw thrustmedial & lateral pterygoid, some masseterLeuka
AD30jaw sidewaysmedial & lateral pterygoid, temporalisLeuka
AU31jaw clenchertemporalis, masseter, medial pterygoidLeuka
AD32purrait dependsAction descriptors
AD33puhaltaait dependsAction descriptors
AD34puffit dependsAction descriptors
AD35imeit dependsAction descriptors
AD36pullistumait dependsAction descriptors
AD37lip wipeit dependsAction descriptors
AU38sierainlaajennindilator naris (alar nasalis)Nose & mid-face
AU39sieraimen kompressoricompressor naris (transverse nasalis) + depressor septiNose & mid-face
AU45vilkkuaorbicularis oculi, palpebral + relaxation of LPSSilmät ja posket
AU46silmäniskuorbicularis oculiSilmät ja posket
korvat ylös ja taakse #notFACSauricular musclesBrows & forehead
silmien räpäytys #notFACSorbicularis oculi, pretarsal palpebralSilmät ja posket
huuliraudat #notFACSorbicularis oris, marginalHuulet

Brows & forehead

AU4 brow lowerer: FACS reference

AU4 otsanlaskija

corrugator supercilii-, depressor supercilii- ja/tai procerus-lihakset.

Action: Kulmien alentaja knits (corrugator supercilii) and lowers (procerus, depressor supercilii, and parts of corrugator supercilii) the brow area and lower central forehead.

Note: Brow lowerer can be performed by any or all of the muscles listed above. Though FACS lumps together the actions of all three muscles, kun opetan kasvojen anatomiaa ja FACS:ää., erotan liikkeet toisistaan.

ears up & back (#notFACS): facial movement reference

korvat ylös ja taakse

#notFACS

auricular muscles (see notes)

Action: Korvat ylös ja taaksepäin nostaa korvat ja työntää ne taaksepäin.

Note 1: This is not a FACS action. I include this ear movement in the FACS-huijauslehti because I see it happen relatively often.

Note 2: There are multiple auricular muscles. The superior auricular moves the ears up. The posterior auricular moves the ears back. The anterior auricular moves the ears forward. At present, I cannot separate these movements. The reference here shows posterior auricular + superior auricular movement.

Silmät ja posket

AU45 blink: FACS reference

orbicularis oculi, palpebral part + relaxation of levator palpebrae superioris

Action: Vilkku sulkee ja avaa silmät nopeasti ja sujuvasti.

Note: Beyond pretarsal activation, vilkkua also often consists of (1) relaxation of levator palpebrae superioris and/or (2) forced closure from the preseptal portion of orbicularis oculi.

AU46 wink: FACS reference

AU46 silmänisku

orbicularis oculi

Action: Vinkki sulkee toisen silmän, yleensä jonkin verran puristettuna.

Read the full note

Note: Unless you are a facial coder conducting behavioral research (and even then, the official FACS Manual lists AU46 wink as “optional”), the FACS shape for wink is not the most useful. I include it because other FACS lists include it; however, I find it to be a clunky, unnecessary addition to most shape sets. That being said, orbicularis oculi does deserve better functional breakdowns beyond cheek raiser, blink, and lid tightener, but wink is not the way to go.

Nose & mid-face

Mid-face landmarks: nasolabial furrow and infraorbital triangle
AU9 nose wrinkler: FACS reference

AU9 nenä ryppyinen

levator labii superioris alaeque nasi (usually co-activates with depressor supercilii and/or procerus)

Action: Nenän rypistelijä nostaa nenän sivuja, sieraimia ja ylähuulen keskiosaa.

Note: The brow lowering you see in nenä ryppyinen ei johdu suoraan levator labii superioris alaeque nasi (LLSAN) -lihaksesta. Pikemminkin sen aiheuttavat otsaa laskevat lihakset, jotka usein ovat pareittain yhteydessä nenä ryppyinen: depressor supercilii ja procerus. Näiden lihasten ja LLSAN-lihaksen välillä on vaihteleva yhteenkytkeytyneisyys.

AU38 nostril dilator: FACS reference

AU38 sierainlaajennin

dilator naris (alar portion of nasalis)

Action: Nenäontelon laajentaja expands and widens the nostril wings, allowing for deeper air intake.

AU39 nostril compressor: FACS reference

AU39 sieraimen kompressori

compressor naris (transverse portion of nasalis) + depressor septi

Action: Nosturin kompressori kaventaa sieraimen siipiä ja samalla usein myös laskee nenän kärkeä.

huulien kulmat

AU13 sharp lip puller: FACS reference

AU13 terävä huulivedin

levator anguli oris

Action: Terävä huultenvetäjä (aiemmin tunnettu nimellä poskipuskuri) draws the lip corners upward.

AU14 dimpler y-axis typesuperior + inferior portions of buccinator: FACS reference
y-akselin tyyppi
superior + inferior portions of buccinator
AU14 dimpler z-axis typeposterior portion of buccinator: FACS reference
z-akselin tyyppi
posterior portion of buccinator
AU14 dimpler y-axis + z-axis typeinferior + superior + posterior portions of buccinator: FACS reference
y-axis + z-axis type
inferior + superior + posterior portions of buccinator

AU14 dimpler

osittain #notFACS

buccinator-lihas

Action: y-axis type: Dimpler pinches the lip corners against each other on a vertical plane.

Action: z-axis type: Dimpler draws the lip corners back against the teeth.

Note: y-axis and z-axis dimplers are not FACS-official terms. Classic FACS describes dimpler y+z-akselin yhdistelmätyyppinä.

AU15 lip corner depressor: FACS reference

AU15 huulten kulman puristin

depressor anguli oris (DAO)

Action: Huulten kulman puristin vetää huulen kulmat alaspäin.

AU18 lip pucker: FACS reference

AU18 huulten nyppyyntyminen

incisivus labii inferioris & incisivus labii superioris

Action: Huulten nyppyyntyminen draws the lip corners medially, causing the fleshy part of the lips to collect toward the midline of the face and protrude.

Note 1: Incisivus labii superioris and incisivus labii inferioris are considered accessory muscles to orbicularis oris.

Note 2: Huulten nyppyyntyminen aktivoi yleensä yhdessä huuliraudat (vertical lip tightener). This example features both huulten nyppyyntyminen ja huuliraudat. See huuliraudat.

AU20 lip stretcher: FACS reference

AU20 huulten venyttäjä

risorius

Action: Huulten ojentaja vetää huulten kulmia sivusuunnassa ja venyttää huulten lihaisaa osaa.

Note 1: Not to be confused with suun venytys, which refers to forced (not due to relaxation) jaw lowering.

Note 2: Risorius is one of the most variable facial muscles in humans. Depending on the study, it has been reported missing in anywhere from 1 to 94% of research subjects. Risorius is narrow and difficult to locate, so this discrepancy may be partly inflated by methodological errors. Jos haluat lisätietoja anatomisesta vaihtelusta, varaa studioluento kasvolihasten monimuotoisuudesta..

Lower lip & chin

AU16 lower lip depressor: FACS reference

AU16 alahuulen painaja

depressor labii inferioris (DLI)

Action: Alahuulen painaja vetää alahuulta alaspäin ja sivusuunnassa.

Huulet

These actions all come from orbicularis oris, the muscle that rings the mouth.

AU8 lips toward each other: FACS reference

AU8 huulet toisiaan kohti

orbicularis oris

Action: Huulet toisiaan kohti tuo ylä- ja alahuulet toisiaan kohti laskemalla ylähuulta ja nostamalla alahuulta.

Note 1: Huulet toisiaan kohti brings the lips back together from actions that may separate them. In this reference, AU26 leuan pudotus separates the lips, and AU8 closes the lips while the jaw stays open.

Note 2: In tools like ARKit and Android XR, AU8 is solely used to counteract the lip opening caused by AU26. On real faces, AU8 is not limited to counteracting jaw opening: it can counteract anything that separates the lips. For instance, if a strong AU9 causes the lips to part, AU8 can bring the lips together while retaining other aspects of AU9.

AU22 lip funneler: FACS reference

AU22 huulten suppiloitsija

orbicularis oris, peripheral part

Action: Huulten suppiloitsija työntää huulet eteenpäin ja puhaltaa ne ulospäin.

AU23 lip tightener: FACS reference

AU23 huulten kiristin

orbicularis oris, marginal part

Action: Huulten kiristin ohentaa huulia. Ajattele, että ylähuuli ja alahuuli romahtavat kumpikin itseensä.

Note: Not to be confused with huuliraudat, which constricts the lips toward the midline of the face.

lip cincher (#notFACS): facial movement reference

huuliraudat

#notFACS

orbicularis oris, marginal part

Action: Huulten kiristysnauha supistaa huulet kohti kasvojen keskiviivaa.

Note: Lip cincher is not in official FACS. I previously called it pystysuora huulen kiristin, since FACS lumps it in with AU23. Only horizontal tightening qualifies as huulten kiristin in original FACS. I separate the two because the lips tighten in distinct manners. Orbicularis oris has rich variation in fiber direction, which yields more potential actions than have been documented so far. The distinction is especially useful when breaking down speech.

AU24 lip presser: FACS reference

AU24 huulten painaja (or “lip pressor”)

orbicularis oris, marginal part

Action: Huulten painaja presses the top and bottom lips against each other.

Read the full note

Note: You may see huulten painaja spelled “lip pressor” in many sources. This variation can be attributed to Paul Ekman’s inconsistent documentation. The FACS Investigator’s Guide from 1978 has one instance of “lip pressor” (on page 6, a page ripe with differently spelled FACS actions such as “lip tightner” for huulten kiristin, “lip puckerer” for huulten nyppyyntyminen, “cheek puffer” for terävä huulivedin, and “lip suck” for huulet imevät). The official 2002 FACS-käsikirja solely uses “lip presser.” To further ail the prescriptivist mind, Ekman’s post-2002 writings (e.g. Mitä kasvot paljastavat, 2005) revert to the 1978 “pressor” spelling. Circa 2020, I asked Ekman’s protégé, Erika Rosenberg, whether “presser” or “pressor” was the canon spelling; her answer was that the spelling mattered less than the attribution of the AU number. The jury is still out, so we’ll have to wait at the edge of our seats for the next release of the FACS-käsikirja ratkaista tämä painamalla asia.

AU28 lips suck: FACS reference

AU28 huulet imevät

orbicularis oris, marginal and peripheral parts

Action: Huulet imevät vetää huulet suuaukkoon ja kietoo ne hampaiden ympärille.

Note 1: AU17 chin raiser appears during the in-between steps. I cannot perform this action without help from AU17 during the transition to the final pose, and mentalis likely shows up during lips suck for many others as well.

Note 2: Leuan pudotus tarvitaan lähes aina huulet imevät.

Leuka

AU26 jaw drop: FACS reference

AU26 leuan pudotus

relaxation of masseter, temporalis, and medial pterygoid

Action: Leuan pudotus lowers the mandible (jaw) in a relaxed (unforced) manner.

AU27 mouth stretch: FACS reference

AU27 suun venytys

lateral pterygoid and the suprahyoid (anterior digastric, geniohyoid, and mylohyoid)

Action: Suun venytys forcefully lowers the mandible (jaw). Unlike AU26, AU27 is not due to relaxation.

Read the full note

Note: Because “mouth” can colloquially refer to the lips and/or the jaw, suun venytys is easily confused with similarly named actions like huulten venyttäjä. Watch the naming in toolkits such as ARKit and ICT-FaceKit, both of which renamed AU20 huulten venyttäjä kuten suun venytys (lol). The suun venytys in ARKit and ICT-FaceKit is not the original suun venytys from FACS. It is unfortunate that suun venytys (1) was named so poorly to begin with, and (2) that ARKit and ICT-FaceKit made it worse with name swapping. A more pointed name like “jaw stretch” would have suited it better. Ultimately, it is what it is, so be careful out there.

AD29 jaw thrust: FACS reference

AD29 jaw thrust

medial & lateral pterygoid and some masseter

Action: Leuan työntövoima pushes the mandible (jaw) forward.

Note: “AD” stands for action descriptor, a less fleshed-out action unit that works more as an event descriptor.

AD30 jaw sideways: FACS reference

AD30 jaw sideways

medial & lateral pterygoid and temporalis

Action: Leuka sivuttain moves the mandible (jaw) to the side (either left or right).

AU31 jaw clencher: FACS reference

AU31 jaw clencher

temporalis, masseter, and medial pterygoid

Action: Leukojen puristin brings the mandible (jaw) upward, pressing it against the upper jaw (maxilla).

Misc

AU21 neck tightener: FACS reference

AU21 kaulan kiristin

platysma

Note: You may see some AU20 lip stretcher in the AU21 kaulan kiristin example and vice versa. This is due to the close relationship between the risorius and platysma muscles.

AU25 lips part: FACS reference

AU25 huulet avautuvat

it depends

Note: In FACS, AU25 huulet avautuvat refers to the state of the lips being parted. Any action that separates the lips can cause it, e.g. relaxation of mentalis, relaxation of orbicularis oris, or contraction of other muscles.

Action descriptors

“AD” stands for action descriptor. An action descriptor is a less fleshed-out action unit (AU). ADs work more as event descriptors than as single muscle actions.

AD19 tongue show: FACS reference

AD19 kieli näyttää

it depends

AD32 bite: FACS reference

AD32 purra

it depends

AD33 blow: FACS reference

AD33 puhaltaa

it depends

AD34 puff: FACS reference

AD34 puff

it depends

AD35 suck: FACS reference

AD35 ime

it depends

AD36 bulge: FACS reference

AD36 pullistuma

it depends

AD37 lip wipe: FACS reference

AD37 lip wipe

it depends

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How to cite this page

For citations to track correctly, please refer to the virallinen tietue Google Scholarissa.

APA

Ozel, M. (2020, helmikuu). FACS-huijauslehti. Kohtaa FACS. https://melindaozel.com/facs-cheat-sheet/

BibTeX

@misc{ozel2020facs,
  author = {Ozel, Melinda},
  title = {FACS Cheat Sheet},
  year = {2020},
  month = feb,
  howpublished = {{\url{https://melindaozel.com/facs-cheat-sheet/}}
}

References & further reading

  1. Hjortsjö, C.-H. (1970). Ihmisen kasvot ja mimiikan kieli. Studentlitteratur.
  2. de Sanctis Pecora, C. (2020). One21: A novel, customizable injection protocol for treatment of the forehead with IncobotulinumtoxinA. Kliininen, kosmeettinen ja tutkimuksellinen ihotautioppi, 13, 127-136. https://doi.org/10.2147/ccid.s237519
  3. Ekman, P., Friesen, W. V., & Hager, J. C. (2002). Kasvojen toimintojen koodausjärjestelmä. Tutkimus Nexus.
  4. Netter, F. H. (2019). Atlas of human anatomy (7. painos). Elsevier.
  5. Standring, S., & Tubbs, S. R. (2025). Gray’s anatomy. Elsevier.

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