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Work · December 31, 2015

Guesstimate

A spreadsheet for things that aren't certain

Guesstimate launched on December 31, 2015 with 286 votes, #41 of 3,505 launches that month and more than 95% of that year's launches. The site was still online in September 2026, 10 years on.

In plain words

Guesstimate is a spreadsheet application designed for planning and analysis when outcomes are uncertain. It uses stochastic models, Monte Carlo simulations, and sensitivity analyses to help users with financial planning, strategic decision-making, and risk assessment. The web-based tool is suited for anyone needing to work with probabilistic data rather than fixed values.

written from the facts on this page · September 2026

From the sources

Plan finances, make strategic decisions, and do risk assessment. Guesstimate uses stochastic models, Monte Carlo simulations, and sensitivity analyses.

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Source: Product Hunt launch ↗

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