Red Bull Racing RB21

{{Short description|2025 Formula One car}}

{{Use dmy dates|date=April 2025}}

{{Racing car

| name = Red Bull Racing RB21

| Constructor = Red Bull Racing (chassis)
Honda Racing Corporation (power unit)

| category = Formula One

| designer = {{Ubl

| Pierre Waché (Technical Director)

| Ben Waterhouse (Chief Engineer, Performance)

| Paul Monaghan (Chief Engineer, Car Engineering)

| Craig Skinner (Chief Designer)

| Jerome Lafrage (Chief Engineer, Composites and Structures)

| Edward Aveling (Chief Engineer, Mechanical and Systems)

| Enrico Balbo (Head of Aerodynamics)

}}

| predecessor = Red Bull Racing RB20

| Team = Oracle Red Bull Racing

| chassis =

| engine name = Honda RBPTH003{{Cite web |date=15 February 2024 |title= Honda RBPTH003|url=https://honda.racing/f1/machines/honda-rbpth-003 |access-date=20 February 2024 |website=Honda Racing |language=en}}

| configuration =

---

{{convert|1.6|L|cuin|0|abbr=on|lk=on}}

direct injection V6 turbocharged engine limited to 15,000 rpm in a rear mid-mounted, rear-wheel-drive layout

| electric motor = Honda Kinetic and thermal energy recovery systems

| battery = Honda Lithium-ion battery

| Power = 1,020 hp (750 kw)

| Weight = 800 kg (including driver, excluding fuel)

| fuel = Esso / Mobil Synergy

| lubricants = Mobil 1

| tyres = Pirelli P Zero (Dry)
Pirelli Cinturato (Wet)

| front suspension = Multi-link pull-rod actuated dampers and anti-roll bar

| rear suspension = Double wishbone push-rod springs, dampers, and anti-roll bar

| Drivers = {{ubl|{{0}}1. {{flagicon|NED}} Max Verstappen|30. {{flagicon|NZL}} Liam Lawson|22. {{flagicon|JPN}} Yuki Tsunoda}}

| Debut = 2025 Australian Grand Prix

| First_win = 2025 Japanese Grand Prix

| Last_win = 2025 Japanese Grand Prix

| Last_event =

| Races = {{sum|{{F1cstat|RBR|entries}}|-394}}

| Wins = {{sum|{{F1cstat|RBR|wins}}|-122}}

| Podiums = {{sum|{{F1cstat|RBR|podiums}}|-282}}

| Poles = {{sum|{{F1cstat|RBR|poles}}|-103}}

| Fastest_laps = {{sum|{{F1cstat|RBR|fastestlaps}}|-99}}

| image = 2025 Japan GP - Red Bull - Yuki Tsunoda - Qualifying.jpg

| caption = Yuki Tsunoda driving the RB21 in a one off livery during the {{F1GP|2025|Japanese}}

| Image_size = 270px

}}

The Red Bull Racing RB21 is a Formula One car designed and constructed by Red Bull Racing currently competing in the 2025 Formula One World Championship. It is being driven by defending World Champion Max Verstappen, who is joined by Liam Lawson and Yuki Tsunoda, the latter replacing Lawson from the Japanese Grand Prix. The RB21, which is powered by the Honda RBPTH003 power unit, is the last Red Bull Racing car to be powered by Honda RBPT-badged engines; from the {{f1|2026}} season, Red Bull and its sister team Racing Bulls will utilise Red Bull Powertrains Ford engines.{{Cite web |date=3 February 2023 |title=Ford announces F1 return in 2026 with Red Bull |url=https://www.espn.com/f1/story/_/id/35581477/ford-announces-return-formula-one-2026-red-bull |access-date=5 February 2023 |website=ESPN.com |language=en |archive-date=5 February 2023 |archive-url=https://web.archive.org/web/20230205021315/https://www.espn.com/f1/story/_/id/35581477/ford-announces-return-formula-one-2026-red-bull |url-status=live }}

The RB21 is the first Red Bull Racing car since the RB2 to not be designed by former Chief Technical Officer Adrian Newey, and the first car to be designed by Technical Director Pierre Waché who is now overseeing all aspects of any future Red Bull challengers from design to production with the RB21 being the first car for which he oversaw both the design and production process.