How to run an online hackathon: timing, channels and submissions.

In three cases:

• when participants study or work and can't stop for two days;
• when they are based in different cities or offices;
• when you want more finished work than one night produces.

Venue, food and travel drop out, and people who can't travel can still join.

It fits less well if you want colleagues from one office to get to know each other, or you need an event with a story to tell. In that case consider a hybrid: online work, in-person final.

Longer than an in-person event, because people work around other commitments. The right length depends on who takes part:

Decide on the time people really have, not on a standard length. If you only need ideas, not prototypes, a short format is enough. With students, use the gap between two exam periods and check the university calendar. The example plan at the end of the page uses a 3-week build: replace it with your own length.

If everything runs through one channel, announcements drown in questions. Keep four separate spaces:

1. Announcements: one-way, only organizers post. Deadlines, changes, reminders.
2. Q&A: open to everyone. Answer here rather than in private messages, so everyone gets the same answer. In a hiring challenge that is a fairness issue.
3. Team coordination: the space where each team organizes itself.
4. Resources: brief, data, templates, mentor contacts.

Mentors work in shifts, posted in announcements with times and names. Plan several office-hour slots and one mid-event check-in, to catch blockers before they reach the submission. Step up support in the final days: that is when questions about formats and files arrive.

Decide it in the rules before sign-ups open: people register as teams, register alone, or form teams in the first days. Meeting people online is hard: without dedicated time, people who arrive alone stay alone.

• Kickoff with short intros. Anyone with an idea or looking for teammates introduces themselves in one minute. Then people split into breakout rooms by topic.
• Written proposals in advance. Have people read the proposals beforehand. Each person picks one project. Then you move a few people to balance teams. If everyone gets several votes, you risk picking projects nobody really wants to build.
• A team deadline, for example the end of day three. After that, solo participants work alone or join a team with a free seat.

On MARA people take part alone or in teams. MARA does not match people: how teams form is set by the challenge rules, which the organizer decides. In a team-based hiring challenge, ask for a short note on each person's contribution (see the judging criteria).

Run a full simulation of the participant journey up to submission and leave time to fix what breaks. In the example plan below, the test happens 2 weeks before. Run it with a test account and with someone who did not build the event:

• Journey: test sign-up, login, brief, team and uploading a test submission.
• Access: check that links, files and data open from company networks, university networks and phones.
• Video call: check that the tool handles the headcount you expect at kickoff.
• Personal data: check that each tool is GDPR-compliant. List every tool that processes participant data (platform, video, chat, forms) and its vendor, then check with your adviser or data protection officer.

• Date, time and zone on every deadline: "Friday 20 November, 6 pm CET (5 pm UTC)". The EU changes clocks on the last Sunday of March and of October, and other countries change on other dates. If the challenge spans a change, write CET or CEST and add UTC.
• No all-nighters. Online doesn't need them: set hours people can keep and still sleep.
• A staffed deadline. Expect many submissions in the last hours. Set the deadline when someone on your team is online, for example 6 pm on a weekday, not midnight.
• Employees: work and submit within working hours, respecting the shifts of people who don't work Monday to Friday.
• Students: they often work evenings and weekends, so cover those slots with at least one mentor shift.

Start from the submissions you want and work backwards:

sign-ups needed = submissions you want ÷ share of sign-ups who submitted last time

The share comes from your previous edition: submissions divided by sign-ups. Use your own data, not an average from somewhere else: employees, students and job candidates behave differently.

For live sessions, such as the kickoff call or a final, run the same calculation with the share of sign-ups who joined last time. Don't use it to estimate submissions: joining a call and submitting work are different things.

Example with made-up numbers, to replace with yours. Last time 120 people signed up and 30 submitted: 25%. For 40 submissions you need 160 sign-ups. If 70% of sign-ups join the kickoff, expect about 112 people on the call.

If this is your first edition, you have no share of your own. Set a minimum number of sign-ups and a date by which you decide whether to postpone or widen promotion. Afterwards, keep the sign-up and submission counts: on MARA the participant list and submissions export to Excel or ZIP.

Most of the work arrives in the last days, and early submitters often keep editing until the end. Plan the close:

1. Reminders: in announcements one week, two days and three hours before.
2. Late-submission rule: already in the rules, applied the same way to everyone.
3. Eligibility check: does each submission meet the rules and format? Work out the hours and book them right after the deadline: eligibility hours = submissions × minutes per submission ÷ 60. Example with values to replace: 40 submissions × 4 minutes = 160 minutes, or 2 hours 40 minutes. Time yourself on a test submission to get your own minutes.
4. Judging: work out each judge's time with the formula in the guide to hackathon judges. When there are many submissions, plan a shortlist of finalists and a judging window with fixed dates.
5. Winners: on a date announced in advance, with feedback to every team against the criteria and a certificate for everyone who submitted.

This is an example: copy the table and swap in your own timing, dates and names. In the example, promotion starts 6 weeks before the start.

MARA is software with AI to create and run practical challenges, hackathons included.

• Builder: describe the problem and MARA AI writes the brief, rules, criteria, deliverables and timeline. You edit everything and nothing goes live until you approve.
• Access: you can publish the challenge to the MARA student community, growing with partner universities, or keep it closed: reserved for a university's students, who sign in with their university email, or for whoever receives the private link. Alone or in teams.
• During: a workspace, announcements and Q&A for each challenge, submissions in one place.
• After: a participant list with statuses your people set, individual notes you can send to everyone who submitted, export to Excel or ZIP. Everyone who submits gets a verifiable certificate and a portfolio.

Your people evaluate, on criteria fixed before publishing: judges enter the workspace, see the submissions and update the statuses. MARA gives no scores and does not rank anyone. A public challenge is visible to the MARA student community, on top of your own channels. For live sessions such as kickoff and awards, plan a video call tool.

You pay the subscription only while a challenge is live: Launch is €67 a month for 1 live challenge, Growth €109 a month for 3 live challenges at once. Drafts are free and unlimited. VAT excluded. No publishing fee and no fee per participant. The other cost lines are in how much a hackathon costs.

A real example: H-FARM's H-ACK "Robots in Action", a 24-hour hackathon held on 11 and 12 April 2026, ran end to end on MARA: 157 participants, 30 teams, 6 judges (source: H-FARM College article). Participants collaborated, organized their work and submitted their projects inside MARA. Read the case or go back to the home page.

• H-FARM College, "Beyond the CV: MARA, the platform born from the challenges of H-FARM College" (H-ACK figures). college.h-farm.com