Dozens of photos from the 2019 Oscars red carpet

Red ruffles, pink tulle and even gold gowns inspired by Oscar himself have overrun the Academy Awards red carpet, as Hollywood glitterati showed off their fineries during cinema's biggest glam-fest.

Matching the colour of the world's most famous carpet was the attention-getting choice for many attendees.

Call it crimson, scarlet or vermillion, the red gowns popped under sunny skies and a mild California breeze as a steady cavalcade of stars entered Hollywood's Dolby Theatre.

Lady Gaga brought old Hollywood glamour in an Alexander McQueen black gown, leather gloves and a 128 carat diamond from Tiffany, as Emma Stone's coppery Louis Vuitton gown with futuristic shoulders was covered in sparkling paillettes.

Frontrunner to win Best Actress, The Wife star Glenn Close chose a shimmering gold Carolina Herrera tunic dress - with four million beads, the actress noted - with a heavy flowing train, setting the evening off on the right note in an ode to Oscar, the coveted gold statuette.

"My God, how much does it weigh?" gasped E! host Ryan Seacrest, who struggled to lift her train.

"42 pounds (19 kg)!" enthused Close.

While pink made a major play, red ruffles were the choice of a bevy of actresses, including best supporting nominee for Roma Marina de Tavira.

But the theme was taken to the next level by Green Book star Linda Cardellini whose oversized flounce of red ruffles cascaded in layers down her body, cinched together with a pink belt.

Singer Jennifer Hudson's elegant Elie Saab gown featured a red ruffle that slithered from one shoulder down to a slit at the side.

Recent Grammy winner Kacey Musgraves also chose oversized ruffles in her princess-like Giambattista Valli, with two poofs of pink tulle at the shoulder.

"Make way for the dress, I need about ten feet," she warned.

Angela Bassett was easy to spot in electric pink by Reem Acra whose gargantuan bow at the shoulder was worthy in itself of an award.

Most outrageous - yet still perfectly in keeping with Oscar chic - was Pose star Billy Porter, who wore a black velvet tuxedo gown designed by Christian Siriano, the top a classic tuxedo with a built-in bodice and the bottom a full, dramatic sweep of fabric.

Making a milder choice was singer Adam Lambert, who performed with Queen. He wore an orchid on the lapel of his Tom Ford tuxedo with oversized cuffs and a dramatic swirling diamond earring completing the look.

Best Director nominee Spike Lee was one of the first to arrive, setting the tone for colour in a purple suit, matching purple glasses, purple chauffeur's cap and gold Jordans.

Australian Associated Press