Rate limiting , allows you to set limits on data throughput in a bursty environment such as a
typical network.

Cisco recommends the following values for the normal and extended burst parameters:

Burst-normal = configured rate * 1/8 * 1.5 seconds (1/8 for convert bit to byte)
Burst-max = Burst-normal * 2
!

Calculated Configuration in Place :
Configured rate divide /5.33 = Burst-normal
Burst-normal = * 2 = Burst-max

For Example
!
rate-limit {input | output} [dscp dscp-value] [access-group [rate-limit] acl-index] bps burst-normal
burst-max conform-action conform-action exceed-action exceed-action
!
rate-limit output 496000 93000 186000 conform-action transmit exceed-action drop

496000 = 400Kbps
93000 =    93Kbps
186000 =  186Kbps

Configured Command :

2000000 = 2Mbps
375000    =  375Kbps
750000    = 750Kbps

Input Rule :

rate-limit input access-group 198 2000000 375000 750000 conform-action transmit exceed-action drop

Output Rule :

rate-limit output access-group 199 2000000 375000 750000 conform-action transmit exceed-action drop

Create ACL for rate-limit INPUT rule :

access-list 198 permit ip 192.168.1.0 0.0.0.255 any

Create ACL for rate-limit OUTPUT rule :

access-list 199 permit ip any 192.168.1.0 0.0.0.255

input : Applies this CAR traffic policy to packets received on this input interface.
output : Applies this CAR traffic policy to packets sent on this output interface.

The traffic must conform to these numbers in order for the router to transmit it (as specified by conform-action transmit).
If the traffic exceeds those bandwidth settings, the router will drop it (as specified by exceed-action drop).

E.G :

8000000 = 8Mbps
1500000 = 1.5Mbps
3000000 = 3Mbps

rate-limit input access-group 198 8000000 1500000 3000000 conform-action transmit exceed-action drop
rate-limit output access-group 199 8000000 1500000 3000000 conform-action transmit exceed-action drop

More Example :

Rate-Limit on DSL line on WAN interface for Incoming Traffic :

ip access-list extended 199
access-list 199 permit ip any any

!

Assign Rate-Limit to interface :

int d0
rate-limit input access-group 199 5000000 930000 1870000 conform-action transmit exceed-action drop

!
!
Rate-Limit on DSL line on LAN interface for Incoming Traffic :

ip access-list extended 198
permit ip 192.168.19.192 0.0.0.15 any
permit ip 172.16.0.0 0.0.0.3 any

Assign Rate-Limit to interface :
int vlan 1
rate-limit input access-group 199 5000000 930000 1870000 conform-action transmit exceed-action drop