Even in the codeine-drenched, genre-fluid rap world fans live in today, the radio freestyle remains an immutable polygraph test for raw skill and mic presence.

If listeners can feel you off the strength of only what you bring to that radio show—which is, optimistically speaking, a hefty dose of charisma and an unreleased verse from a new album—you've got an energy that can't be recreated by record labels or nullified by fickle trends. Over the last few decades, artists have created indelible moments in rap history through impromptu freestyles at radio stations across the country, either fortifying or creating the foundation for their legacy in the process.

For his part, Harlem's Big L earned his bones in part through freestyles that would become the stuff of legend. In 1995, he pulled up on The Stretch Armstrong and Bobbito Show for another of his live rhyme sessions that would inevitably be quoted for all eternity. For this occasion, he also brought along Jay-Z, who was months away from dropping his debut album, Reasonable Doubt. Attacking Miilkbone's "Keep It Real" instrumental, the two unloaded quick-fire flows and deft metaphors for a freestyle that acted as a snapshot of what was and what would soon be: L was the current king of the underground, but Jay would be joining him soon.

Another artist who made waves with on-air freestyles was Eminem, who first earned his reputation with rap battling before he gained just as much respect for radio exhibitions. Armed with a nearly breathless flow and a reflexive ability to snatch the nearest rhymable word like a venus fly-trap captures its lunch, the Music to Be Murdered By em served up a at least a dozen quotable bars during a 1997 freestyle for 92.3's The Wake Up Show. From that point on, months later, in 1998, Em would sign with Dr. Dre's Aftermath label, and the rest is history.

Hov, Big L and Em aren't the only folks to deliver memorable freestyles. Jadakiss, Cam'ron, Nas, Ghostface Killah, Meek Mill and more have also made time to serve up rhyme sessions that will be remembered forever.

Today, XXL takes a look at 23 of the best radio freestyles in rap history.

Big L and Jay-Z Destroy Stretch and Bobbito Show 

Year: 1995
Radio Show: The Stretch Armstrong and Bobbito Show

Jay-Z Bodies DJ Khaled and Kanye West's "Grammy Family"

Year: 2006
Radio Show:  Funkmaster Flex on Hot 97

Black Thought Eviscerates Mobb Deep's "The Learning (Burn)"

Year: 2017
Radio Show:  Funkmaster Flex on Hot 97

The Notorious B.I.G. Delivers Effortless Bars for His Final Freestyle 

Year: 1997
Radio Show:  92.3's The Wakeup Show

Eminem Detonates on LL Cool J's "4, 3, 2, 1" With Proof

Year: 1999
Radio Show: Tim Westwood

Meek Mill Comes Full Circle by Freestyling on Drake's "Back to Back" 

Year: 2018
Radio Show: Funkmaster Flex on Hot 97

Eminem and Royce 5'9" Bring Bad Meets Evil to Stretch and Bobbito

Year: 1998
Radio Show: The Stretch Armstrong and Bobbito Show

The Notorious B.I.G. and Craig Mack Pay Tim Westwood a Visit

Year: 1994
Radio Show: Tim Westwood - Radio 1 Rap Show

 Roc-A-Fella Records Takes Over Hot 97

Year: 2001
Radio Show: Hot 97

Eminem Blacks Out for XL Freestyle

Year: 1998
Radio Show: XL Radio

Jadakiss Revisits 2008 BET Hip-Hop Awards Cypher Beat 

Year: 2009
Radio Show: 92Q

Jadakiss Rips Nas' "It Ain't Hard to Tell"

Year: 2004
Radio Show: 
Hot 97

Cassidy Destroys Jay-Z's "Public Service Announcement" and More for 11-Minute Freestyle

Year: 2004
Radio Show: Hot 97

Big L's '98 Freestyle

Year: 1998
Radio Show: The Stretch Armstrong and Bobbito Show

G-Unit Disses Shyne and Lil Kim

Year: 2003
Radio Show:
Hot 97 with Funkmaster Flex

Pusha-T Does Justice to Prodigy's "Keep It Thoro"

Year: 2012
Radio Show: Hot 97 With Funkmaster Flex

Nas Gives a Glimpse of the Future on Stretch and Bobbito

Year: 1993
Radio Show: The Stretch Armstrong and Bobbito Show

Fabolous Debuts With N.O.R.E. on "Money Power Respect" Beat

Year: 1998
Radio Show:
Hot 97 With DJ Clue

J. Cole's Bodies Funkmaster Flex Freestyle

Year: 2013
Radio Show:Hot 97 with Funkmaster Flex

G.O.O.D. Music Kill a Group Freestyle

Year: 2012
Radio Show: Hot 97 With Funkmaster Flex

Big L, a Young Cam'ron and Ma$e Hit Up Stretch and Bobbito

Year: 1996
Radio Show: The Stretch Armstrong and Bobbito Show

The Lox Tackle Jay-Z's "So Ghetto"

Year: 2002
Radio Show:  Hot 97 with Funkmaster Flex

Royce 5'9" Gives a Lesson

Year: 2020
Radio Show:  L.A. Leakers on Power 106

See 17 of the Best Rap Record Label Compilation Albums

More From KOOC-FM