| artist,genre,country | |
| I AM ABOVE ON THE LEFT,RIO/Avant-Prog,Russia | |
| I AM THE ARCHITECT,Post Rock/Math rock,Germany | |
| I AM THE MANIC WHALE,Crossover Prog,United Kingdom | |
| I AM THREE PEOPLE,Heavy Prog,Finland | |
| I AM WAITING FOR YOU LAST SUMMER,Post Rock/Math rock,Russia | |
| I AND THOU,Neo-Prog,United States | |
| I BOW CANDLES,Heavy Prog,Multi-National | |
| I GIULLARI DI CORTE,Rock Progressivo Italiano,Italy | |
| I HEAR SIRENS,Post Rock/Math rock,United States | |
| I HEARD FROM LAVINIA,Crossover Prog,Italy | |
| I KNOW YOU WELL MISS CLARA,Jazz Rock/Fusion,Indonesia | |
| I LIKE TRAINS,Post Rock/Math rock,United Kingdom | |
| I VIAGGI DI MADELEINE,Heavy Prog,Italy | |
| I WAS GIVEN FEET TO FOLLOW YOU,Post Rock/Math rock,United States | |
| I WILL KILL CHITA,Post Rock/Math rock,Russia | |
| LE,RIO/Avant-Prog,France | |
| I.AB,Crossover Prog,United States | |
| I.C.U.,Symphonic Prog,Germany | |
| I.D. COMPANY,Eclectic Prog,Germany | |
| I.E.M.,Psychedelic/Space Rock,United Kingdom | |
| IAKO BEI,Crossover Prog,Slovakia | |
| IAMTHEMORNING,Crossover Prog,Russia | |
| IANVA,Rock Progressivo Italiano,Italy | |
| IBARAKI,Tech/Extreme Prog Metal,United States | |
| IBIO,Prog Folk,Spain | |
| IBIS,Rock Progressivo Italiano,Italy | |
| IBIS,Jazz Rock/Fusion,Sweden | |
| IBLISS,Krautrock,Germany | |
| ICARUS,Jazz Rock/Fusion,United Kingdom | |
| ICE,Neo-Prog,Netherlands | |
| ICE AGE,Progressive Metal,United States | |
| ICEBERG,Jazz Rock/Fusion,Spain | |
| ICEBURN,Experimental/Post Metal,United States | |
| ICED INK,Eclectic Prog,United States | |
| ICEFISH,Progressive Metal,Multi-National | |
| ICHTHYANDER DAD'S ONLY DOLPHIN,Eclectic Prog,Ukraine | |
| ICI MAINTENANTS,Psychedelic/Space Rock,United Kingdom | |
| ICONIC SKY,Crossover Prog,United Kingdom | |
| ICONOCLASTA,Jazz Rock/Fusion,Mexico | |
| ICSIS,RIO/Avant-Prog,France | |
| ICYCORE,Progressive Metal,Italy | |
| ID,Psychedelic/Space Rock,United States | |
| TH D,Neo-Prog,Multi-National | |
| IDEAMEN,Progressive Metal,United States | |
| IDEE CONFUSE,Heavy Prog,Italy | |
| IDENTIFIED,Experimental/Post Metal,United States | |
| IDIOT FLESH,RIO/Avant-Prog,United States | |
| IDIOT SAINT CRAZY,Experimental/Post Metal,France | |
| GIUSEPP ELASI,Progressive Electronic,Italy | |
| IF,Jazz Rock/Fusion,United Kingdom | |
| IF THESE TREES COULD TALK,Post Rock/Math rock,United States | |
| IFSOUNDS / EX IF,Crossover Prog,Italy | |
| IGAYON,Crossover Prog,Israel | |
| IGNATIUS,Crossover Prog,Spain | |
| IGNATZ,Krautrock,Belgium | |
| IGNEA,Progressive Metal,Ukraine | |
| IGORRR,Experimental/Post Metal,France | |
| IGRA STAKLENIH PERLI,Psychedelic/Space Rock,Yugoslavia | |
| IGZIT-NINE,Jazz Rock/Fusion,Japan | |
| IHLO,Progressive Metal,United Kingdom | |
| IHRE KINDER,Krautrock,Germany | |
| IHSAHN,Tech/Extreme Prog Metal,Norway | |
| III MILĘNIO,Symphonic Prog,Brazil | |
| TH KAN METHOD,Neo-Prog,Italy | |
| IKARUS,Zeuhl,Switzerland | |
| IKARUS,Eclectic Prog,Germany | |
| IKIHEVONEN,Psychedelic/Space Rock,Finland | |
| IKUINEN KAAMOS,Tech/Extreme Prog Metal,Finland | |
| IL BUCO DEL BACO,Rock Progressivo Italiano,Italy | |
| IL PORTO DI VENERE,Rock Progressivo Italiano,Italy | |
| IL TESTAMENTO DEGLI ARCADI,Rock Progressivo Italiano,Italy | |
| ILENKUS,Tech/Extreme Prog Metal,Ireland | |
| ILIAD,Jazz Rock/Fusion,United States | |
| ILIENSES,Prog Folk,Italy | |
| DJORDJ LIJIN,Psychedelic/Space Rock,Yugoslavia | |
| ILL WICKER,Prog Folk,Sweden | |
| ILLŔCHIME QUARTET,Eclectic Prog,Italy | |
| TH LLNESS,Experimental/Post Metal,United States | |
| ILLOGICIST,Tech/Extreme Prog Metal,Italy | |
| ILLUMINAE,Crossover Prog,United Kingdom | |
| ILLUMINATED MINERVA,Progressive Metal,Canada | |
| ILLUMINATI,Tech/Extreme Prog Metal,Romania | |
| ILLUMION,Neo-Prog,Netherlands | |
| ILLUSION,Progressive Metal,United States | |
| ILLUSION,Eclectic Prog,United Kingdom | |
| ILLUSION OF GRAVITY,Neo-Prog,Italy | |
| ILLUSION SUITE,Progressive Metal,Norway | |
| ILLUSIVE LIGHT,Crossover Prog,Germany | |
| ILOUS & DECUYPER,Prog Folk,France | |
| ILUVATAR,Neo-Prog,United States | |
| ILUZJON,Crossover Prog,Poland | |
| ILVCIA,Symphonic Prog,Spain | |
| ILYDAEN,Post Rock/Math rock,Belgium | |
| IMAGERY,Heavy Prog,Brazil | |
| IMAGES,Eclectic Prog,France | |
| IMAGES OF EDEN,Progressive Metal,United States | |
| IMAGIN'ARIA,Heavy Prog,Italy | |
| IMAGINAERIUM,Neo-Prog,United Kingdom | |
| IMAHORITSUNEOYOSHIDATATSUYA,RIO/Avant-Prog,Japan | |
| IMÁN CALIFATO INDEPENDIENTE,Jazz Rock/Fusion,Spain | |
| IMANISSIMO,Psychedelic/Space Rock,Indonesia | |
| BRIA MIG,Prog Folk,United States | |
| IMMANENT,Progressive Metal,France | |
| IMMANU EL,Post Rock/Math rock,Sweden | |
| IMMINENT SONIC DESTRUCTION,Progressive Metal,United States | |
| IMMORTAL ONION,Eclectic Prog,Poland | |
| IMMUNE,Crossover Prog,United Kingdom | |
| IMPACT FUZE,Jazz Rock/Fusion,Russia | |
| IMPERIAL TRIUMPHANT,Tech/Extreme Prog Metal,United States | |
| IMPLOSION,Progressive Metal,Greece | |
| IMPROVED SOUND LIMITED,Krautrock,Germany | |
| IMPULS,Jazz Rock/Fusion,Czech Republic | |
| IMPULSO DE LOS SONIDOS INCONSCIENTES,Heavy Prog,Argentina | |
| IN A NUTSHELL,Psychedelic/Space Rock,Russia | |
| IN ABSTRACKTO,Eclectic Prog,Mexico | |
| IN CONTINUUM,Crossover Prog,United States | |
| IN EACH HAND A CUTLASS,Post Rock/Math rock,Singapore | |
| IN GOWAN RING,Prog Folk,United States | |
| IN GRIEF,Tech/Extreme Prog Metal,Norway | |
| IN HUMAN FORM,Tech/Extreme Prog Metal,United States | |
| IN LIMBO,Crossover Prog,France | |
| IN LINGUA MORTUA,Tech/Extreme Prog Metal,Norway | |
| IN LOVE WITH,RIO/Avant-Prog,France | |
| IN MORPHEUS' ARMS,Progressive Metal,Germany | |
| IN MOURNING,Tech/Extreme Prog Metal,Sweden | |
| IN NOMINE,Neo-Prog,Spain | |
| IN OCEANS,Heavy Prog,United Kingdom | |
| IN SEARCH FOR,Progressive Metal,Belarus | |
| IN SPE,Symphonic Prog,Estonia | |
| IN THE LABYRINTH,Prog Folk,Sweden | |
| IN THE NAME,Progressive Metal,Canada | |
| IN THE PRESENCE OF WOLVES,Heavy Prog,United States | |
| IN THE WAKE OF GIANTS,Post Rock/Math rock,United States | |
| IN THE WOODS...,Experimental/Post Metal,Norway | |
| IN VAIN,Tech/Extreme Prog Metal,Norway | |
| IN ZAIRE,Psychedelic/Space Rock,Italy | |
| IN(OUR)FINITE SPACE,Post Rock/Math rock,Canada | |
| IN-DREAMVIEW,Post Rock/Math rock,United States | |
| IN.OVO,Experimental/Post Metal,Canada | |
| INCANDESCENT SKY,Psychedelic/Space Rock,United States | |
| INCOMING CEREBRAL OVERDRIVE,Experimental/Post Metal,Italy | |
| TH NCREDIBLE STRING BAND,Prog Folk,United Kingdom | |
| L NCREÍBLE FUGA DE TRIÁNGULOS,RIO/Avant-Prog,Argentina | |
| INDACO,Prog Folk,Italy | |
| INDELIBLE,Crossover Prog,Norway | |
| INDEPENDĘNCIA,Progressive Metal,Brazil | |
| INDEX,Symphonic Prog,Brazil | |
| INDEXI,Crossover Prog,Yugoslavia | |
| INDIAN SUMMER,Heavy Prog,United Kingdom | |
| INDIGNU,Post Rock/Math rock,Portugal | |
| INDIGO,Symphonic Prog,Germany | |
| INDIGO,Prog Related,Austria | |
| INDISCIPLINE,Heavy Prog,Canada | |
| INDISCIPLINED LUCY,Neo-Prog,Sweden | |
| INDRICOTHERE,Tech/Extreme Prog Metal,United States | |
| INDUKTI,Experimental/Post Metal,Poland | |
| INES,Neo-Prog,Germany | |
| INFAMIA,Tech/Extreme Prog Metal,Italy | |
| INFANTEPHANT,RIO/Avant-Prog,United States | |
| INFERA BRUO,Tech/Extreme Prog Metal,United States | |
| INFICTIONS,Crossover Prog,United Kingdom | |
| INFINIEN,Eclectic Prog,United States | |
| INFINITE HORIZON,Progressive Metal,Germany | |
| INFINITE MONOPOLY,Crossover Prog,United States | |
| INFINITE ORCHESTRA,Crossover Prog,United States | |
| INFINITE SPECTRUM,Progressive Metal,United States | |
| INFINITE THIRD,Post Rock/Math rock,United States | |
| TH NFINITE TRIP,Psychedelic/Space Rock,United Kingdom | |
| INFINITOME,Symphonic Prog,United States | |
| INFINITY,Symphonic Prog,United States | |
| INFINITY FORMS OF YELLOW REMEMBER,Psychedelic/Space Rock,United Kingdom | |
| INFINITY WINDOW,Progressive Electronic,United States | |
| INFLUENCE X,Progressive Metal,Switzerland | |
| L NFONIE,RIO/Avant-Prog,Canada | |
| INFRINGEMENT,Neo-Prog,Norway | |
| INFRONT,Heavy Prog,Russia | |
| INFUSION KAMACHUI,Crossover Prog,Argentina | |
| INGENIUM,Tech/Extreme Prog Metal,Poland | |
| INGRANAGGI DELLA VALLE,Rock Progressivo Italiano,Italy | |
| INGURGITATING OBLIVION,Tech/Extreme Prog Metal,Germany | |
| INI,Tech/Extreme Prog Metal,Norway | |
| INIOR,Neo-Prog,Italy | |
| INISTEKAR,Eclectic Prog,Canada | |
| INITIAL GRAVITY,Progressive Metal,Argentina | |
| INITIAL MASS,Heavy Prog,United States | |
| INITIAL POINT,Tech/Extreme Prog Metal,United States | |
| INNATE CONCEPT,Progressive Metal,Germany | |
| INNER DRIVE,Jazz Rock/Fusion,Russia | |
| INNER EAR BRIGADE,RIO/Avant-Prog,United States | |
| INNER LIGHT ORCHESTRA,Eclectic Prog,Finland | |
| INNER ODYSSEY,Progressive Metal,Canada | |
| INNER PROSPEKT,Crossover Prog,Italy | |
| INNER QUEST,Progressive Metal,Italy | |
| TH NNER ROAD,Symphonic Prog,United Kingdom | |
| INNER SPACE,Jazz Rock/Fusion,Multi-National | |
| INNERSPACE,Crossover Prog,Canada | |
| INNO,Progressive Metal,Italy | |
| INNOSENSE,Progressive Metal,Greece | |
| INOMATA TAKESHI & SOUND L.T.D.,Psychedelic/Space Rock,Japan | |
| INQUIRE,Symphonic Prog,Germany | |
| INQUISITOR,Tech/Extreme Prog Metal,Lithuania | |
| INSIDE THE SOUND,Progressive Metal,Ukraine | |
| INSIDE//OUTSIDE,RIO/Avant-Prog,United States | |
| INSIDER,Psychedelic/Space Rock,Italy | |
| INSONAR,RIO/Avant-Prog,Italy | |
| INSPIRATIONAL CORNER,Crossover Prog,Austria | |
| INSTANT CURTAIN,Eclectic Prog,Italy | |
| INSTANT DRONE FACTORY,Krautrock,Multi-National | |
| INSTANT FLIGHT,Psychedelic/Space Rock,Multi-National | |
| INSTANT SUPPRESSION,Progressive Metal,Russia | |
| TH NSTITUTE OF MODERN LOVE,Neo-Prog,United Kingdom | |
| INTENSITY,Progressive Metal,Greece | |
| INTENTIONAL TRAINWRECK,Progressive Metal,United States | |
| INTENTIONS,Crossover Prog,Netherlands | |
| INTER ARMA,Experimental/Post Metal,United States | |
| INTERFACE,Eclectic Prog,Japan | |
| INTERFERENCE SARDINES,RIO/Avant-Prog,Canada | |
| INTERGALACTIC TOURING BAND,Crossover Prog,Multi-National | |
| INTERKOSMOS,Psychedelic/Space Rock,Austria | |
| INTERNATIONAL HARVESTER,Psychedelic/Space Rock,Sweden | |
| INTERNATIONAL KARATE,Post Rock/Math rock,Australia | |
| INTERPOSE+,Eclectic Prog,Japan | |
| INTERVALS,Tech/Extreme Prog Metal,Canada | |
| INTHEBACKGROUND,Post Rock/Math rock,United States | |
| INTO ETERNITY,Tech/Extreme Prog Metal,Canada | |
| INTO MY HOUSES,Progressive Metal,Finland | |
| INTO THE GREAT DIVIDE,Progressive Metal,United States | |
| INTO THE MOAT,Tech/Extreme Prog Metal,United States | |
| INTO THE PRESENCE,Crossover Prog,United States | |
| INTONATE,Tech/Extreme Prog Metal,Canada | |
| INTRAVENUS,Jazz Rock/Fusion,Greece | |
| INTROITUS,Neo-Prog,Sweden | |
| INTRONAUT,Experimental/Post Metal,United States | |
| INTROVISIÓN,Heavy Prog,Costa Rica | |
| JAC NTVELD,Symphonic Prog,United States | |
| INUS,RIO/Avant-Prog,United States | |
| INVALIDS,Post Rock/Math rock,United States | |
| INVASIVE SPECIES,Heavy Prog,United States | |
| INVERNADERO,Psychedelic/Space Rock,Chile | |
| INVERTIGO,Neo-Prog,Germany | |
| TH NVINCIBLE CZARS,Eclectic Prog,United States | |
| INVISIBLE,Symphonic Prog,Argentina | |
| TH NVISIBLE BAND!,Psychedelic/Space Rock,United Kingdom | |
| INVISIBLE OPERA COMPANY OF TIBET (BRAZIL),Psychedelic/Space Rock,Brazil | |
| TH NVISIBLE PRESENCE,Crossover Prog,Multi-National | |
| INVISIGOTH,Neo-Prog,United States | |
| INVOLVED,Progressive Electronic,United States | |
| IO,Experimental/Post Metal,United Kingdom | |
| IO EARTH,Crossover Prog,United Kingdom | |
| IOMAIR,Progressive Metal,Canada | |
| ION,Crossover Prog,United Kingdom | |
| ION,Experimental/Post Metal,United States | |
| ION DISSONANCE,Tech/Extreme Prog Metal,United States | |
| ION QUEST,Psychedelic/Space Rock,United States | |
| IONA,Prog Folk,United Kingdom | |
| IOSEB,Post Rock/Math rock,Sweden | |
| IOTUNN,Tech/Extreme Prog Metal,Denmark | |
| IQ,Neo-Prog,United Kingdom | |
| L RA DE DIOS,Psychedelic/Space Rock,Peru | |
| L RA DEL BACCANO,Heavy Prog,Italy | |
| IRAKLIS,Prog Folk,Greece | |
| IREPRESS,Experimental/Post Metal,United States | |
| IRIS,Neo-Prog,France | |
| IRIS DIVINE,Progressive Metal,United States | |
| IRISH COFFEE,Heavy Prog,Belgium | |
| IRMIN'S WAY,Krautrock,Multi-National | |
| IRON BUTTERFLY,Proto-Prog,United States | |
| IRON DUKE,Symphonic Prog,Denmark | |
| IRON KIM STYLE,Jazz Rock/Fusion,United States | |
| IRON MAIDEN,Prog Related,United Kingdom | |
| IRON THRONES,Tech/Extreme Prog Metal,United States | |
| IRONWOOD,Experimental/Post Metal,Australia | |
| IRREVERSIBLE,Experimental/Post Metal,United States | |
| IRRGARTEN,Crossover Prog,Canada | |
| JOH RVINE,Jazz Rock/Fusion,United Kingdom | |
| ISBJÖRG,Neo-Prog,Denmark | |
| ISILDURS BANE,Symphonic Prog,Sweden | |
| ISIS,Experimental/Post Metal,United States | |
| ISKANDER,Eclectic Prog,Germany | |
| ISLAND,Eclectic Prog,Switzerland | |
| ISLAND,Tech/Extreme Prog Metal,Germany | |
| ISLANDS,Crossover Prog,Canada | |
| ISLE OF THE CROSS,Tech/Extreme Prog Metal,United States | |
| ISOBAR,Eclectic Prog,United States | |
| ISOLATION,Prog Folk,United Kingdom | |
| ISOPODA,Symphonic Prog,Belgium | |
| ISOS,Crossover Prog,Canada | |
| TH SOSCELES PROJECT,Tech/Extreme Prog Metal,Canada | |
| ISOTOPE,Jazz Rock/Fusion,United Kingdom | |
| ISOTOPES,Tech/Extreme Prog Metal,United States | |
| ISPROJECT,Rock Progressivo Italiano,Italy | |
| ISTHMUS,Experimental/Post Metal,United States | |
| ISZIL,Crossover Prog,Chile | |
| IT,Neo-Prog,United Kingdom | |
| IT,Eclectic Prog,United States | |
| IT BITES,Crossover Prog,United Kingdom | |
| IT'S A BEAUTIFUL DAY,Proto-Prog,United States | |
| IT'S NOT NIGHT: IT'S SPACE,Psychedelic/Space Rock,United States | |
| IT'S THE END,Eclectic Prog,Norway | |
| IT'S.TRUE.MENTALITY,Progressive Metal,Poland | |
| ITERUM NATA,Prog Folk,Finland | |
| ITHACA,Prog Folk,United Kingdom | |
| ITOIZ,Prog Folk,Spain | |
| ITZIAR,Prog Folk,Spain | |
| IV LUNA,Progressive Metal,Italy | |
| IVANHOE,Progressive Metal,Germany | |
| VELISLA VANOV,Neo-Prog,Bulgaria | |
| IVERSEN,Progressive Electronic,Norway | |
| IVIRON,Eclectic Prog,Germany | |
| IVOR AXEGLOVITCH,RIO/Avant-Prog,Denmark | |
| IVORY,Psychedelic/Space Rock,Germany | |
| IVORY TOWER,Progressive Metal,Germany | |
| IWRESTLEDABEARONCE,Tech/Extreme Prog Metal,United States | |
| IX,Eclectic Prog,Venezuela | |
| IXION,Neo-Prog,Netherlands | |
| IXT ADUX,Eclectic Prog,United States | |
| IXTHULUH,Psychedelic/Space Rock,Austria | |
| IZ,Heavy Prog,United States | |
| IZAH,Experimental/Post Metal,Netherlands | |
| IZUKAITZ,Prog Folk,Spain | |
| IZVIR,Jazz Rock/Fusion,Yugoslavia | |
| IZZ,Symphonic Prog,United States | |