Weight Classes

In common with other robot combat events, Robot Wars competitor robots were split into several weight classes (also known as weight categories) at various instances throughout the show's history. Although the first series included robots from multiple weight classes, subsequent series generally only included heavyweight robots in the main competition, with robots from other weight classes participating in their own separate events and championships.

Most of the weight classes seen in the televised UK show were first introduced in the original 1994-1997 US competitions run by Marc Thorpe. The original weight limits used for earlier UK series were also derived from the then most up-to-date iteration of the US competition rules.

List of Weight Classes

Pre-TV

The original 1994 US competition was open to robots in three weight classes: heavyweight, middleweight and lightweight. The minimum and maximum weight limits for those classes were as follows:

Weight Class	Minimum Weight	Maximum Weight
Lightweight	10lbs	40lbs
Middleweight	41lbs	70lbs
Heavyweight	71lbs	100lbs

The first major changes were introduced in the 1995 competition, with altered limits for all existing categories and the introduction of a super lightweight class. The latter was available to robots which had previously been built to the lowest possible weight allowances in the lightweight category.

Weight Class	Minimum Weight	Maximum Weight
Super Lightweight	0lbs/2lbs	20lbs
Lightweight	21lbs	40lbs
Middleweight	41lbs	80lbs
Heavyweight	81lbs	160lbs

For 1996, the limits for all weight classes were adjusted again, with the super lightweight category becoming the more familiarly-known featherweight class.

Weight Class	Minimum Weight	Maximum Weight
Featherweight	5lbs	25lbs
Lightweight	26lbs	50lbs
Middleweight	51lbs	100lbs
Heavyweight	101lbs	165lbs

A final set of changes was implemented for the 1997 event, with an increased minimum weight limit for featherweight robots and an increased maximum for standard heavyweight competitors. The following limits, as listed in a July 1997 capture of the US Robot Wars website, were applicable to each category:

Weight Class	Minimum Weight	Maximum Weight
Featherweight	10lbs	25lbs
Lightweight	26lbs	50lbs
Middleweight	51lbs	100lbs
Heavyweight	101lbs	170lbs

At some point, the upper heavyweight limit was increased further to 175lbs, though no archived captures of the US Robot Wars website from August 1997 exist. However, later captures, along with accounts from various team websites, mention 175lbs as the upper limit, suggesting that it was likely implemented as a last-minute change.

Changes for the cancelled 1998 event were to have included a higher 180lb limit for heavyweights, and a 350lb upper limit for heavyweight walkers. The aforementioned changes are also present in a 'Rules & Guidelines' document dated from 1999, suggesting that there were likely to be retained for the also-cancelled Robot Wars '99 event.

Series 1-7 and Extreme

The main competition of Series 1 was open for robots in four categories: featherweight, lightweight, middleweight and heavyweight. The limits for these were largely based on those issued for the 1997 US competition, including the amended 175lb upper limit for heavyweights. Weights were converted from pounds (lbs) to kilograms (kg) without rounding up. The original TV series limits for each of the above classes were as follows, and remained in effect up until after Series 4:

Weight Class	Minimum Weight	Maximum Weight
Featherweight	Approx. 2.3kg (5lbs)	11.4kg (25lbs)
Lightweight	11.4kg (25lbs)	22.7kg (50lbs)
Middleweight	22.7kg (50lbs)	45.4kg (100lbs)
Heavyweight	45.4kg (100lbs)	79.4kg (175lbs)

In The Second Wars, a super heavyweight category was established along with a dedicated championship shown partially during the Grudge Matches special. No upper limit appears to have been strictly enforced or set in the official build rules; merely, the category was primarily open to robots weighing over the standard heavyweight limit. The heaviest robot known to have competed in this class, Roter Ochse, weighed in at 166.1kg. Series 2 also marked the introduction of dedicated side competitions for the lighter weight categories, leaving heavyweights as the centre focus of the main UK Championship.

Some competitors from Series 1-4 were given some leniency; it was not uncommon for heavyweights to weigh a few kilograms over their official weight limit in those series. Being classified as a heavyweight on the show, Series 1 competitor Barry also notably broke the limit by weighing 116.9kg, which would have rendered it a super heavyweight in later series. Further complicating this issue was the frequent mention of the heavyweight limit being '80kg' on the show and in official documentation; one example of the latter being the statement/application form for the qualifiers of UK Series 4.

For the untelevised American Robot Wars 2000 pilot, the heavyweight limit was increased to 95kg (approximately 209.4lbs) as stated in an official Mentorn announcement. The upper weight limit for domestic competitors in the concurrently-filmed UK Series 4 remained unchanged, however, resulting in three of the US representatives in the War of Independence special weighing substantially more than their UK opponents.

The weight limits were increased from Extreme 1 onwards, which also saw the introduction of the antweight class. An 'Extreme Weight' class was also added to the build rules for Series 5, effectively succeeding the Super Heavyweight category. However, no 'Extreme Weight' events took place, and it is unknown whether any robots were built for the category. The new minimum and maximum limits, effective between Extreme 1 and Series 7, were as follows (bold indicates metric measurements applicable to UK, Dutch and German series filmed during this time):

Weight Class	Minimum Weight	Maximum Weight
Antweight	0g	150g
Featherweight	1kg/2.2lbs	12kg/26lbs
Lightweight	12kg/26lbs	25kg/55lbs
Middleweight	25kg/55lbs	50kg/110lbs
Heavyweight	50kg/110lbs	100kg/220lbs
Extreme Weight (unused)	100kg/220lbs	200kg/440lbs

Walkerbots/Shufflebots

To encourage creativity, walkerbots were allowed to enter one weight class below their actual weight, or weigh up to 200kg in the heavyweight competition (136kg/300lb prior to Series 5/Extreme 1, or 350lbs/160kg in US Season 1-2). Both rules originated from the 1995-1997 US competitions; the latter imposed a maximum upper heavyweight limit of 200lbs (1995-1996) or 300lbs (1997).

No weight bonuses were known to have been applied to super heavyweight walkers. Some walkerbots, however, such as Jim Struts and Millennium Bug, still weighed closer to the heaviest super heavyweights at 175.9 and 160kg respectively.

Shufflebots, a derivative of walkerbots, were originally classified as walkers in their own right and given the same weight limit as traditional types in the heavyweight category. This was until Series 6, where shufflebots were no longer eligible for the increased weight allowance. However, some shufflebots, notably later versions of Ansgar, were still built to the 200kg limit.

Series 8-10

The weight limit for conventional robots was increased again for Series 8, 9 and 10. A single heavyweight class was implemented, though at least one middleweight competitor would also compete in the main UK Championship. The corresponding weight limits for walkerbots and shufflebots were similarly altered, with the former types receiving a substantially lower allowance over conventional designs than in previous series.

Weight Class	Conventional	Walkerbot	Shufflebot
Heavyweight	110kg	135kg	120kg

In Series 10, the weight limits for heavyweight walkerbots and shufflebots were both increased, to encourage more robots of their kind to be built for the rebooted series. Additionally, a featherweight class was proposed and announced as part of the initial application process for this series. However, due to scheduling issues, their reintroduction was subsequently postponed and the series was once again dedicated entirely to heavyweight events. Despite this, the updated featherweight limits were still included in the Series 10 build rules alongside the amended heavyweight limits:

Weight Class	Conventional	Walkerbot	Shufflebot
Featherweight (proposed)	13.6kg	17.6kg	15.1kg
Heavyweight	110kg	145kg	125kg

Pre-TV Champions

In most cases, the 1994-1997 US competitions featured separate Face-Off and Melee tournaments for all available weight classes. The former would be analogous to the domestic championships that formed the basis for most versions of the televised show. A number of 1995 and 1996 battles would be highlighted in official media released for the UK Series, namely the American Robot Wars 1996 and American Robot Wars Final 1996 VHS releases.

Featherweight/Super Lightweight

• 1995: KMM (Face-Off & Melee)
• 1996: Wedge of Doom (Face-Off)
• 1996: The X-2 (Melee)
• 1997: Wedge of Doom (Face-Off & Melee)

Lightweight

• 1994: Julie-Bot (Face-Off)
• 1994: Bloodletter (Melee)
• 1995: Test Toaster One (Face-Off)
• 1995: Kitty Puff Puff (Melee)
• 1996: Attiller (the Hun) (Face-Off)
• 1996: Speed Bump (Melee)
• 1997: Defiant (Face-Off & Melee)

Middleweight

• 1994: The X-1
• 1995: La Machine (Face-Off & Melee)
• 1996: Agamemnon (Face-Off & Melee)
• 1997: Vicious-1 (Face-Off)
• 1997: Turtle Roadkiller (Melee)

Heavyweight

• 1994: Ramfire 100
• 1995: The Master & Blendo (Face-Off)*
• 1995: La Machine (Melee)**
• 1996: BioHazard (Face-Off)
• 1996: La Machine (Melee)
• 1997: BioHazard & Blendo (Face-Off & Melee)*

*Blendo was awarded co-champion status in exchange of forfeiting due to safety concerns in Face-Off tournaments. **Competed as a middleweight entry.

UK Champions

From Series 2 onwards, the main competition was intended solely for heavyweight competitors, which meant that robots from other weight classes had to enter their own separate competitions. Series 2 featured competitions for all the other weight classes (except the Antweight class, which was not introduced until Extreme 1), but these competitions became less frequent in subsequent series and were mainly restricted to special events shown as part of Robot Wars Extreme and Series 7.

Antweight

Main article: Antweight Championship

• Series 3: Event cancelled
• Extreme Series 1: Combatant
• Extreme Series 2: Anty B

Featherweight

Main article: Featherweight Championship

• Series 2: Demolisher
• Series 3: Event cancelled
• Extreme Series 1: Beef-Cake
• Extreme Series 2: Argh!
• Series 7: DTK

Lightweight

Main article: Lightweight Championship

• Series 2: Slippery Strana
• Series 3: Event cancelled
• Extreme Series 1: Event cancelled
• Extreme Series 2: Typhoon Thunder

Middleweight

Main article: Middleweight Championship

• Series 2: Hard Cheese
• Series 3: Event cancelled
• Extreme Series 1: Typhoon
• Extreme Series 2: Typhoon
• Series 7: Typhoon

Heavyweight

Main article: UK Championship

• Series 1: Roadblock
• Series 2: Panic Attack
• Series 3: Chaos 2
• Series 4: Chaos 2
• Series 5: Razer
• Series 6: Tornado
• Series 7: Typhoon 2
• Series 8: Apollo
• Series 9: Carbide
• Series 10: Eruption

Super Heavyweight

Main article: Super Heavyweight Championship

• Series 2: Kick Robut
• Series 3: Event cancelled

Trivia

• A universal 100kg weight limit was originally proposed by Steve Carsey for both competitor and House Robots in the UK Series. However, this was scrapped when Chris Reynolds raised concerns that this would adversely affect the costs and operational requirements of the latter.
• According to a 1999 Tinweb discussion forum, an upper limit of 125kg was reportedly set for the proposed Series 3 Super Heavyweight Championship. Multiple teams - including Team Power and Team Rolling Thunder - were contacted about this change before filming began, though the Super Heavyweight Championship would end up being cancelled following a behind-the-scenes accident.