Voice over IP

Call Centre: What is a Dialer and what are the types of Dialers

This article gives a glimpse of what a Dialer is and why it is used in Call Centers, an introduction to various types of Dialers : Manual Dialing, Preview Dialing, Predictive Dialing and Progressive Dialing including the advantages and dis-advantages of each type.  

What is a Dialer?

Dialer is an application used in call centres to automate the process of dialing to external phone numbers so that the agents can attend to certain calls selectively. Well, since call centres want to increase the productivity per agent they have employed, they monitor the time which is spent by an agent to talk to a prospective customer. So, when the agents are provided with a data base and asked to call to various prospects, it is noticed that the effective time spent in talking to the customers is very low as many calls are not picked up, answered by fax machines, busy etc. So, the agents spend more time dialling numbers than actually talking. That is why many outbound call centres employ dialers that automatically dials the phone numbers on behalf of the agents, to increase their efficiency, which is sometimes measured in Talk Time per Hour (TTH).

Types of Dialer’s:

Manual Dialer: There is a phone, there is a phone line connected to it. So, the agents just pick up the phone and start dialing by themselves! It has been noticed that this is the least efficient way of conducting outbound call campaigns in larger call centres (based on Talk Time per Hour values). But we’ll tell you one thing: This is the most economical way for a very small call centre/ office!

Preview Dialing: This is first level of Dialer automation. There is a database in a PC and the agent selects which number to dial to, and perhaps clicks on the contact (or uses some other button) so that the call is automatically dialed by the system and the agent doesn’t have to dial through a keypad. Based on the response, the agent either talks to the person at the other end or manually disconnects the call if there is an answering machine, fax machine, busy signal or no response. The records need to be manually updated by the agent, after the call.

Predictive Dialing:

A predictive dialer consists of a dialing algorithm that “predicts” when an agent will be available and calls being made automatically by the predictive dialer based on the above prediction to have it ready to connect the agent’s workstations when there is an answer by a live contact.

The effectiveness of a predictive dialer depends on a lot of factors like the size of the call centres (number of agents), length of an average call, sophistication of prediction algorithm, time of the day, type of job etc.

If a call is ready (based on the prediction algorithm) and no agent is available, then the call is automatically terminated by the predictive dialer, which results in call abandonment.

A predictive dialer automatically identifies answering machines based on the length of the response immediately after the call is picked up: If it is a short “hello” then it probably is a live contact, if there is a longer response, then it is probably an answering machine. Some predictive dialer’s use frequency detection of the voice answering the call to identify if it is a live contact (person) or an answering machine, which is more effective.

Advantages and dis-advantages of Predictive dialing: Predictive dialer’s are found to be very effective for larger call centres and they may result (on an average) in a better Talk Time per Hour for the agents (More efficiency). The main dis-advantage would be the abandoned calls, which can be tracked with a caller ID and the delay that takes place during the transfer of the call to the agent (after the contact answers, which might prompt the contact to cut the call). This may not be effective for Business to Business Calling unless customized (as the calls may be picked up by an IVR, receptionist or a voice mail).

Progressive Dialing:

In this method, the agent indicates his/her availability and only after the indication by the agent, the progressive dialer starts dialing automatically from the database. There on, the progressive dialer determines if the call resulted in a busy signal, no-answer, fax machine, modem signal etc. and automatically terminates the call (In certain cases, marks the call/record to be called after ‘n’ minutes) and places the call to the next prospect. If any of the above cases is not true, then the agent gets to decide if it is a live call or the call is being answered by an answering machine. If it is a live call, then the agent starts talking to the contact right after the word “Hello” and if it is an answering machine, the agent manually updates (by clicking a button etc.) the database and after that the progressive dialer starts calling the next record automatically.

Advantages and dis-advantages of Progressive dialing: There are no abandoned calls by using a progressive dialer and there is also no delay meaning the agent can start talking to the contact immediately after the contact answers with a “Hello”. Agent might also get some time to preview the details about the contact while the progressive dialer is dialing the number (at least the pronunciation of the name). Progressive dialing is better suited for Business to Business dialing. The dis-advantages include lesser Talk Time per Hour (Lesser efficiency), longer duration taken for each call and the agent has to manually distinguish if the call is answered by an answering machine or a live contact to update the database.


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  • srinivasan

    i want to know about dialer,actually i am BE WITH MCSE COURSE guy,i get an offer as dialer associate in medium size bpo can i take this or not,wheather it is networking field or not,plz reply as soon as possible.

    • admin

      I am not sure what exactly is the job profile for Dialer associate – Maintaining a dialer? Get more details about what you are expected to do on the job – you can ask this during interview.

  • jeet

    i like this a lot it is very interesting and awesome knowledge can u arrange more knowledge about it (specially call center process)on my mail id.

  • shiva

    i am working in small organization as dialer administrator. i want know more information about dialer. can get grow my career with this designation? suggest me please…

  • vaibhav

    Thanks for nice information.
    I want information about hosted dialler.
    Please send it on my mail id. Please

  • Bhavana

    This section only covers the most basic knowledge of what a Dialer is and types of dialing basis the standard model.
    The Dialer as a machine has evolved over a period of time and they work on several platforms. Malita for instance is the aged one while Aspect has ongion 7.1 version in the market. Compaines like Noble has also picked up the international market. Some of them have a huge server while some of them are Web based and some are also based on Clound computing. I think details and features of these dialers is also incredible. Also, not only from the boundaries of the basic functionality of the Dialer to dial, there are various reporting features and live feeds to review.

  • Jitesh R

    In india, Most outbound dialing are using preview dialing as it carry less cost & high data security (In India, a seperate CRM used to check the customer details & complete data does not available on the dialer .).

  • subha

    What’s the cost of a dialler in Indian currency ?

    Which type of dialler should i use for a new call center to be started next month?

  • varun

    hy i wanna know more about diler and within a short period m using new calcentre so i wanna ibformation about it……

  • Anonymous

    hi i have an opportunity to job in a a company his requirements is that the employee must have the knowledge of call center setup what is the networking process of call centre.. will you please help me……