Articles written by
Ben Costantini

This week I read about a hackathon claiming 6,000 attendees over a single weekend. The venues hosting it can’t accommodate more than 1,000 people. Nobody in the comments asked how the math worked. That gap between the claim and the room is what this article is about. For most event organizers, event metrics are marketing, not measurement. Once you understand how attendance numbers are built, why ROI stays a black box, and why matchmaking is often bad on purpose, you’ll read every post-event press release differently. Here’s a decoder. The vocabulary nobody explains to you The event industry has precise definitions. It just doesn’t advertise them. UFI, the global association of the exhibition industry, publishes calculation standards and auditing rules for all of them. Independent bodies like ABC audit against them. Here’s the short version. Visitor. One human being who came to the event. If I attend all three days, I’m one visitor. Visit. One entry through the doors. My three days now count as three visits. UFI accepts both figures in its audits, defines visits as visitors plus repeat visits, and requires the term used to be clearly indicated on the audit certificate. Guess which number ends up on the homepage. Attendee / participant. No standard definition. These are the marketing words. They can mean visitors, visits, registrants, exhibitor staff, speakers, press, students or the organizer’s own team, in any combination. When you read “50,000 participants,” you’re reading a number with no agreed method behind it. Registrant. Someone who signed up. Free registration events love this one, because no-show rates of 30 to 50 percent are common and registrations cost nothing to inflate. Exhibitor. Elastic too. UFI distinguishes direct exhibitors, who contract with the organizer, from co-exhibitors, who are part of a shared stand (think country pavilions). Both count. Daily exhibitor. A company present for a single day, typical in startup zones and rotating programs. A startup using a shared booth on day 2 only counts as one exhibitor, exactly like the anchor brand that paid for 400 sqm across the full show. Pavilion / delegation. A block of space booked by one entity, usually a national export agency, a region or a corporate, then filled with smaller companies. One contract, one invoice, 25 logos. Pavilions are how organizers cluster small booths into themed areas, and how “1,200 exhibitors” can describe wildly different realities. Net vs. gross exhibition space. Net is the square meters actually rented. Gross includes aisles, catering areas and that giant entrance arch. As a rule of thumb: net space is 50% of gross space at an average show.  The prosumer padding One more layer on the attendance side. Many events count audiences that are professional on paper only. Student groups bused in for the afternoon. Employees of a corporate partner who run one workshop on day 3. Startup founders’ plus-ones. Locals with a discounted badge. I’m not saying these people have no place at events. Some of the best energy on a show floor comes from them. But if you’re an exhibitor paying for access to buyers, a headline number that mixes procurement directors with second-year students is not relevant. Ask for the audience breakdown by profile. If the organizer can’t produce one, that tells you something too. The ROI black box Here’s the uncomfortable part: almost nobody wants to know if an event actually performs. CEIR, the research arm of the U.S. industry association IAEE, paused its exhibitor spend research for years and only resumed it in late 2025. Its 2026 Marketing Spend Decision Report finds that management evaluates exhibition ROI mainly on lead volume and post-show closed deals, and documents a gap between what practitioners track and what leadership actually cares about. The industry’s reference dataset on exhibitor spending had not been refreshed since 2017. Read that again: the largest B2B marketing channel went eight years without updated benchmarks. The exhibitor side confirms the fog. Vendelux’s 2026 B2B Events Survey of 120+ marketing and events leaders found that 86 percent can’t accurately attribute ROI to events, and 98 percent struggle to justify event spend to leadership. Yet 80 percent are maintaining or growing their sponsorships anyway.  Organizers benefit from this fog. Some only release their data points after the event is over, when your booking decision for next year is already locked in early-bird pricing. Others share nothing beyond the headline number. Try asking for the seniority breakdown of last edition’s visitors, or the ratio of buyers to service providers walking the aisles. I wrote before that founders systematically underestimate what events cost them, hence my 2:1 preparation rule. The other side of that equation is just as broken: they can’t estimate what events return, because the data to do so is withheld. The GDPR excuse When pushed, some organizers invoke GDPR as the reason they can’t share more. Let’s be precise. GDPR restricts sharing personal data: names, emails, badge scans tied to individuals. It says nothing about aggregated, anonymized statistics. “42 percent of our visitors have purchasing authority” contains zero personal data. An organizer who can’t tell you that either doesn’t know it or doesn’t want you to know it. Neither answer is reassuring. If startups are solving it, ask why organizers aren’t A whole category of companies now exists to answer a question organizers could answer themselves: was this event worth it? Full disclosure: at Sesamers we’re building mytradeshow.ai on this exact gap, so I have a horse in this race. Here are five others working the same seam: Sit with the logic for a second. Organizers gather and process the registration data, the badge scans, the floor plans, the exhibitor contracts. They are the best-placed actors in the world to measure event performance. If third parties have to reconstruct that picture from the outside, it’s because the people holding the data have decided that transparency isn’t always in their interest. Bad matchmaking is a feature One last thing, and it’s my favorite. Whenever an event’s matchmaking is mediocre, don’t […]

The second half of 2026 is packed. Between July and December, there are more than 30 confirmed events worth your time across Europe, the US, and the Middle East, covering everything from AI infrastructure to retail tech, cybersecurity, developer tools, and the full founder-investor circuit. This is not a list of every conference. It’s a selection built around a single filter: does this event put you in a room with people who can move your company forward? Use it as a planning tool, not a bucket list. A mediocre event on the right date still costs you more than three days OOO. GITEX AI Europe 2026 📍 Berlin, Germany  |  🗓 30 Jun–1 Jul 2026 GITEX AI Europe returns to Messe Berlin for its second edition, bringing together 25,000+ tech and business leaders, 1,400+ global enterprises and startups, and 600+ investors from over 100 countries. The event runs four co-located programs: AI Everything Europe for real-world AI applications, North Star Europe for startups with a €50,000 equity-free pitch prize, GISEC Europe for cybersecurity, and GITEX Quantum Expo for quantum commercialisation. The first edition in 2025 drew 21,650 attendees and 755 startups.gitexeurope.com RAISE Summit 2026 📍 Paris, France  |  🗓 8–9 Jul 2026 RAISE Summit 2026 brings together 9,000+ AI leaders, founders, investors and policymakers at the Carrousel du Louvre in Paris, with 350 speakers, enterprise AI discussions, a startup competition with a €10M+ prize pool, and an AI hackathon drawing 7,000 developers. The 2026 edition adds an invitation-only CxO Summit for Fortune 1000 executives, with closed-door sessions featuring executives from Mercedes, AXA, and Capgemini. Speaker lineup includes Yann LeCun, Mark Cuban, and representatives from OpenAI, Anthropic, and NVIDIA. raisesummit.com Love Tomorrow Summit 2026 📍 Boom, Belgium  |  🗓 23 Jul 2026 The fifth edition of Love Tomorrow Summit takes place on 23 July 2026 at De Schorre in Boom, Belgium, the same site as Tomorrowland, on the Thursday between its two festival weekends. The 2026 theme is the future of intelligence: exploring how AI, leadership, and human resilience interact as technological systems accelerate. The Summit brings together 7,000+ attendees across six programming pillars: Impact Entrepreneurship, Natural Intelligence, Science & Technology, Socio-Economic Perspectives, Health & Mindfulness, and Entertainment. There is no equivalent format anywhere on the calendar: a serious impact investing roundtable that ends with a festival. lovetomorrow.com LEAP 2026 📍 Riyadh, Saudi Arabia  |  🗓 31 Aug–3 Sep 2026 LEAP 2026 takes place at the Riyadh Exhibition and Convention Center in Malham, bringing together global technology leaders, startups, investors, entrepreneurs, and government organizations from around the world. The 2025 edition hosted 201,000 visitors, 1,800+ exhibitors, and 1,900+ investors with a combined AUM exceeding $22 trillion. LEAP has grown into one of the few places outside Silicon Valley and Europe where you access truly deep pools of sovereign and institutional capital. Not a startup networking event in the typical sense. Worth the trip if MENA or Gulf markets are on your roadmap. onegiantleap.com TechBBQ 2026 📍 Copenhagen, Denmark  |  🗓 26–27 Aug 2026 TechBBQ 2026 takes place at the Bella Center Copenhagen on August 26–27, bringing together 10,000+ founders, investors, and innovators from across Europe and beyond. Forbes named TechBBQ one of the hottest startup events in Europe for 2026. The event features dedicated matchmaking, pitch competitions, and a strong life sciences program, particularly valuable given Denmark’s outsized position in European biotech and pharma. The format is known for its deliberately warm, hygge-infused atmosphere: the kind of event where meaningful conversations actually happen rather than badge-scan exchanges. Side events run across Copenhagen throughout the week. techbbq.dk IFA Berlin 2026 📍 Berlin, Germany  |  🗓 4–8 Sep 2026 IFA 2026 takes place at Messe Berlin from 4 to 8 September. In its 102nd year, one of the most established consumer electronics and home appliances trade shows globally draws 215,000+ visitors from 140 countries and 1,800+ exhibitors. IFA Next is the dedicated startup zone connecting early-stage companies with investors, global retailers, and tech media. For hardware founders, consumer tech builders, and anyone touching smart home, AI devices, or connected mobility, this is a commercial platform rather than a networking conference. The distinction matters: you come here to sell and to be discovered, not to collect business cards. ifa-berlin.com Infobip Shift 2026 📍 Zadar, Croatia  |  🗓 13–15 Sep 2026 Infobip Shift 2026 takes place September 13–15 in Zadar, bringing together developers and engineers from around the world. The 2026 edition welcomes confirmed speakers from NVIDIA and Apple, with central themes covering cutting-edge technology platforms, career growth in tech, and practical AI tools. The 2025 edition gathered 5,500 attendees from 40 countries. The format rewards founders building technical products who need direct access to engineering talent and developer community: the conference where a junior developer can have a casual coffee with a Netflix senior engineer. Relaxed Mediterranean setting, serious technical content. shift.infobip.com Big Data & AI Paris 2026 📍 Paris, France  |  🗓 15–16 Sep 2026 Big Data & AI Paris 2026 takes place 15–16 September at Paris Expo Porte de Versailles, held under the High Patronage of the President of the French Republic. The event describes itself as the meeting place for IT and data decision-makers industrialising AI. The 2026 Advisory Board includes Chief Data & AI Officers from AXA France, Suez, and L’Oréal, alongside the CEO of Hub France IA. The program covers enterprise AI deployment, data infrastructure, and an Advanced Computing Village focused on quantum and HPC. Practical, enterprise-first, and with direct access to the senior buyer community in French tech: if you’re selling data or AI solutions into large organizations, the room here is more relevant than most. bigdataparis.com NRF 2026: Retail’s Big Show Europe 📍 Paris, France  |  🗓 15–17 Sep 2026 NRF 2026: Retail’s Big Show Europe returns to Paris Expo Porte de Versailles with more than 12,000 attendees from over 60 countries, 4,200 brands, 525 exhibitors, and 200 speakers across three days. The event includes a Startup Hub spotlighting the newest retail tech companies and a […]

Most startup founders treat events like they’re going travelling: count the days, block the calendar, done. But event tickets don’t come cheap, and the actual affair can eat into your budget in so many different ways, you’ll be left with a hole in your company wallet. You see, the problem here is a simple case of math: one can’t budget for unforeseen expenses. That’s why we’ve put together a simple formula that founders can tweak to suit their business needs. The 2:1 rule nobody talks about Here’s a simple rule: Every single day at an event requires two full days of preparation. This isn’t bureaucratic overhead, it’s the operational reality of doing events properly. Why does this ratio work? Because events operate on a timeline that’s fundamentally incompatible with how startups work. Most conferences lock speaker slots, booth spaces, and partnership opportunities months in advance. You can’t A/B test them or sprint your way in at the last minute. Scaleups and corporates have dedicated field marketing teams who start preparing months in advance for events. They’ve already mapped the venue, scheduled meetings, and briefed their booth staff. If you show up with two hours of prep, you’re invisible. But why should you set aside two days for every event day? You’ll fill them with research, targeting, outreach, scheduling, content, positioning, logistics operations, internal coordination, and post-event planning.  You can’t change your pitch deck the morning of your panel. Events punish improvisation because the stakes are live and all opportunity windows close fast. That’s why a 2:1 ratio is the minimum buffer you need to make showing up worthwhile. A three-day conference isn’t a three-day commitment; you’ll have to set aside at least six days before factoring in travel, team coordination, or what you’ll actually do at the event. Treat it as the baseline for local events that you’re only attending, too. And when you add distance, team members or booth logistics to the equation, that number explodes. The winning formula Here’s what no event organizer will tell you upfront: Total Time = (Event Days × 2) × Distance Factor × Team Factor × Activity Factor Distance multipliers Team size factors Activity type factors What does it look like in the real world? Let’s run an example scenario: Say you’re exhibiting at Web Summit with two co-founders. Calculation: (3 days × 2) × 1.5 (international) × 1.3 (team of three) × 1.5 (exhibiting) = 17.6 days That’s nearly four working weeks of founder time. Not calendar days — productive working days. An entire sprint. A fundraising cycle. A product release window. That’s before you account for the inevitable chaos: marketing materials might get delayed, or your booth might require a last-minute redesign, or one of your team might fall ill on day two. This matters more than you think Startups don’t fail because they attend too many events. They fail because they attended the wrong events and didn’t realize the true cost until it was too late. Most early-stage founders operate on razor-thin runways and even thinner margins. Losing 17 days to the wrong conference can mean missing a critical hiring window, pushing a launch back by a quarter, or running out of cash. The opportunity cost is immense. Three filters to help you decide Preparation is table stakes, but the real competitive advantage is selection. Before you commit to any event, run it through these three filters: 1. Are your top 10 target customers actually attending? Don’t settle for “the industry will be there,” or “it’s a great brand.” Will the specific people who can write cheques or sign contracts be in the venue? If you can’t name at least five confirmed attendees you want to meet, you’re engaging in speculation, and speculation is expensive. 2. Can you get time with decision makers? Networking is not the same as dealmaking. Conferences are full of people collecting business cards and having “great chats” that go nowhere. Look for pre-scheduled meetings, private roundtables, investor office hours, or curated dinners. If the event doesn’t facilitate structured access, you’re paying to work a room. 3. Does the timing align with your fundraising or launch cycle? Attending a major event two weeks before a funding deadline is fundraising malpractice. Exhibiting at a trade show when your product isn’t ready to demo is theatre, not business development. Timing isn’t everything, but mistimed events have the potential to burn capital and credibility in equal measure. The real decision Preparation is hard, but preparing brilliantly for the wrong event isn’t going to yield the results you’re looking for. The formula above isn’t meant to scare founders away from conferences. If you’re going to invest 17 days of founder time, you’d better know exactly what ROI you’re chasing and have a plan to capture it. Most founders wing it. The folks who don’t tend to be the ones still standing when funding dries up. At Sesamers, we’ve spent years inside the event ecosystem, watching startups burn time and capital on conferences that looked good on paper but delivered nothing. The startups that survive and thrive aren’t the ones who attended the most events; they simply skipped those that weren’t relevant, and attended the right events at the right time, with the right preparation. So before you book your next booth or confirm that speaking slot, do the math, and see if you can afford to go wrong.

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