Every time you have to give a speech or make a presentation, do this calculation

Here’s a practice to develop with regard to your public speaking. It’s something that I started doing many years ago. It’s a simple calculation that should take 30 seconds (or less if you use a calculator) but the result is always powerful and sobering.

Here’s what you do: Take the number of people whom you anticipate will be in the audience and multiply that number by the amount of time you have to speak. So, for example, if you are asked to make a 30-minute presentation to 20 members of your department, the calculation would look like this:

30 minutes x 20 people = 600 minutes

600 minutes = 10 hours

Many speakers think about time only in terms of the length of their speech or presentation.  But in the example above, your 30-minute presentation is not just 30 minutes. It is 30 minutes for the first person in the audience plus 30 minutes for the second person plus 30 minutes for the third person, etc.

The total amount of time would be 10 hours for one person. How valuable is 10 hours of someone’s time? That’s a little more than one working day for most people. If you have 10 hours of someone’s time, you would want to make that time as productive as possible.

You should look at the time your audience is spending with you in the same way. The bigger your audience, the more time you have to speak, the greater the amount of time involved.

Last month, I went to Munich, Germany to give a one-hour talk to approximately 150 managers at Danone, one of the world’s leading food companies. As always, I did the calculation:

1 hour x 150 people = 150 hours

A standard work week is 40 hours. Yes, I know that there are many businesses where the work week is longer—I worked for many years as a lawyer in one of Canada’s leading law firms—but I stick with 40 hours.

So, for my speech, it was as if the company had given me almost an entire month of work time for one person. That’s an incredibly valuable commodity, especially in today’s world. I want to treat that time with as much respect as I can and give as much value as I can for it.

That’s why you should do this calculation. It is a quick way to put things in perspective and remind yourself of your responsibility. Keep in mind that I have limited my calculation to the length of the speech or presentation. In reality, you have to add the time it takes people to get to the speaking venue, return to work or home, get back up to speed on projects or responding to accumulated emails, etc. So the true number is even bigger.

Do this calculation every time you give a speech or make a presentation. It will change, in a good way, how you think about your speaking engagements.

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  1. Dear John, I always use this calculation when I talk about “Beeing on Time”. Multiply the number of people kept waiting with the number of minutes the meeting started late time by 50 (hourly wage – very low calculation) and devide by 60. That is how much money was wasted. It actually does make a difference if one looks at time in proportion to number of people involved.

    1. Thanks for the comment and calculation, Friederike. I know exactly what you are talking about. When I worked in the UN system, I did something similar as so many meetings started late and then meandered past the scheduled finish time with little, if anything, accomplished. It gets depressing if you do it too often! That’s the good thing about the calculation in the post: it is forward-looking, proactive and inspiring. Cheers!

  2. Very sobering numbers, indeed! It’s great that you’re spreading the word about this.
    As you say, it concerns our most important non-renewable resource. That was my opening in this post about presenting online, too.
    (The vast majority of webinars start with at least 5 minutes of time-wasting. Multiply that by the headcount and you get a shocking result, before the useful content has even started – if it ever does!!)

    1. Thanks, Craig. And thanks for sharing your post. Webinars are tricky animals because now you are adding multiple locations, multiple levels of quality in terms of equipment and connectivity and multiple levels of sophistication when it comes to technology. Sending out simple, clear instructions by email to all participants beforehand is one way to avoid some of the delay, but I have yet to see a webinar run completely hitch free. Even the best ones hit some bumps.

    1. Thanks for the comment, Sandra.

      Regarding your question, I believe you are asking whether the formula of 1 hour of preparation for every 1 minute of speaking time is sound. I have given speeches where I prepared much more than 1 hour per minute of speaking time and I have had speeches where I prepared less. A lot depends on well the speaker knows the material, whether he has given part or all of the speech before, etc. To the extent that the 1 hour : 1 minute ratio holds, I would include research and reflecting on the speech as part of the hour in addition to preparing and rehearsal.

  3. Dear John:

    Thanks again, for bringing this necessary and too frequently ignored thought process to attention.
    I have been doing something similar for long time too. Not only when I am speaking, but also when I am in an audience–specially in company Town Halls (or similar).

    I prefer to use the term “person-hours” instead of just “hours” and then multiply it by the average person-hour-salary to compute the cost of participation / investment in the event. You can chose to use a higher $ figure by using billing rate instead of salary. This is the value threshold that has to be crossed, failing which there was an inadequate ROI.

    Most corporate Town Hall meetings do not deliver an acceptable ROI.

    This is a strong argument that can be made for investing top quality presentation coaching.
    Check out this Gil Amelio example https://www.youtube.com/watch?v=PsBVyUDs-84
    The uncomfortable truth is that most town hall talks are far more similar to the Gil Amelio’s effort than we care to admit. It is simultaneously a travesty and an opportunity.

    Keep up your good work … Good Luck … Best Regards … Rashid

    1. Thank you, Rashid, for the comment. I just watched Mickeleh’s video. Very interesting back story from someone who was involved in one Apple’s biggest MacWorld events. Thanks for sharing it.

  4. hi John,

    interesting thought. Another way to look at it is that if 10 corporate people attended your 30-min presentation, then 300 mins of corporate downtime happened. Company needs to know it was worthwhile and speaker should keep that in mind.

  5. Hi John, As always, well said.

    Want to share my positive experience: Since your classes for IOMBA @UNIGE, I try to put all my ideas into 5 min summary. And I see now how difficult it is to listen to watery speeches without head or tail. Thank you for your great job.


    1. Thank you, Olga! Great to hear from you and glad that you have been able to use the techniques that we discussed in class. I wish you continued success with your speeches and presentations. Stay healthy during these uncertain times.

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John delivered a keynote address about the importance of public speaking to 80 senior members of Gore’s Medical Device Europe team at an important sales event. He was informative, engaging and inspirational. Everyone was motivated to improve their public speaking skills. Following his keynote, John has led public speaking workshops for Gore in Barcelona and Munich. He is an outstanding speaker who thinks carefully about the needs of his audience well before he steps on stage.

Karsta Goetze

TA Leader, Gore and Associates

I first got in touch with John while preparing to speak at TED Global about my work on ProtonMail. John helped me to sharpen the presentation and get on point faster, making the talk more focused and impactful. My speech was very well received, has since reached almost 1.8 million people and was successful in explaining a complex subject (email encryption) to a general audience.

Andy Yen

CEO, Proton Technologies

John gave the opening keynote on the second day of our unit’s recent offsite in Geneva, addressing an audience of 100+ attendees with a wealth of tips and techniques to deliver powerful, memorable presentations. I applied some of these techniques the very next week in an internal presentation, and I’ve been asked to give that presentation again to senior management, which has NEVER happened before. John is one of the greatest speakers I know and I can recommend his services without reservation.

David Lindelöf

Senior Data Scientist, Expedia Group

After a morning of team building activities using improvisation as the conduit, John came on stage to close the staff event which was organised in Chamonix, France. His energy and presence were immediately felt by all the members of staff. The work put into the preparation of his speech was evident and by sharing some his own stories, he was able to conduct a closing inspirational speech which was relevant, powerful and impactful for all at IRU. The whole team left feeling engaged and motivated to tackle the 2019 objectives ahead. Thank you, John.

Umberto de Pretto

Secretary General, World Road Transport Organization

I was expecting a few speaking tips and tricks and a few fun exercises, but you went above and beyond – and sideways. You taught me to stand tall. You taught me to anchor myself. You taught me to breathe. You taught me to open up. You taught me to look people in the eye. You taught me to tell the truth. You taught me to walk a mile in someone else’s shoes. I got more than I bargained for in the best possible way.

Thuy Khoc-Bilon

World Cancer Day Campaign Manager, Union for International Cancer Control

John gave a brilliant presentation on public speaking during the UN EMERGE programme in Geneva (a two days workshop on leadership development for a group of female staff members working in the UN organizations in Geneva). His talk was inspirational and practical, thanks to the many techniques and tips he shared with the audience. His teaching can dramatically change our public speaking performance and enable us as presenters to have a real and powerful impact. Thank you, John, for your great contribution!

Sara Canna

HR Specialist, World Health Organization

John is a genuine communication innovator. His seminars on gamification of public speaking learning and his interactive Rhetoric game at our conference set the tone for change and improvement in our organisation. The quality of his input, the impact he made with his audience and his effortlessly engaging style made it easy to get on board with his core messages and won over some delegates who were extremely skeptical as to the efficacy of games for learning. I simply cannot recommend him highly enough.

Thomas Scott

National Education Director, Association of Speakers Clubs UK

John joined our Global Sales Meeting in Segovia, Spain and we all participated in his "Improv(e) your Work!" session. I say “all” because it really was all interactive, participatory, learning and enjoyable. The session surprised everybody and was a fresh-air activity that brought a lot of self-reflection and insights to improve trust and confidence in each other inside our team. It´s all about communication and a good manner of speaking!"

Jon Lopez

General Manager Europe, Hayward Industries

Thank you very much for the excellent presentation skills session. The feedback I received was very positive. Everyone enjoyed the good mix of listening to your speech, co-developing a concrete take-away and the personal learning experience. We all feel more devoted to the task ahead, more able to succeed and an elevated team spirit. Delivering this in a short time, both in session and in preparation, is outstanding!

Henning Dehler

CFO European Dairy Supply Chain & Operations, Danone

Thanks to John’s excellent workshop, I have learned many important tips and techniques to become an effective public speaker. John is a fantastic speaker and teacher, with extensive knowledge of the field. His workshop was a great experience and has proven extremely useful for me in my professional and personal life.

Eric Thuillard

Senior Sales Manager, Sunrise Communications

John’s presentation skills training was a terrific investment of my time. I increased my skills in this important area and feel more comfortable when speaking to an audience. John provided the right mix between theory and practice.

Diego Brait

Director of the Jura Region, BKW Energie AG

Be BOLD. Those two words got stuck in my head and in the heads of all those ADP leaders and associates that had the privilege to see John on stage. He was our keynote speaker at our annual convention in Barcelona, and his message still remains! John puts his heart in every word. Few speakers are so credible, humble and yet super strong with large audiences!

Guadalupe Garcia

Senior Director and Talent Partner, ADP International