• Estimation from the Top-Down-When more information about the project's scope becomes available, this technique is frequently used, in which high-level chunks at the feature or design level are estimated and then broken into smaller chunks or work-packets as more information becomes available.
• Estimation from the Ground Up-When the requirements are understood at a discrete level, this technique is utilised to estimate the total project by aggregating the smaller workpieces. When the information is only known in bits and pieces, this is the method to use.
• Analogous Estimation--When there is a reference to a similar project that has been completed and it is easy to correlate with other projects, this project estimation technique is applied. To arrive at a project estimate, experts' judgement and historical information from similar operations in a referenced project are gathered.
• Estimation using Parametrics-Independent quantifiable variables from the project work are used in this technique.
• Estimation in three points-The weighted average of an optimistic, most likely, and pessimistic estimate of the work package is used in this strategy. This is commonly referred to as the PERT (Program Evaluation and Review Technique).
• Analyze What-If-Impact analysis is a project estimation technique that uses assumptions based on a variety of elements such as scope, duration, cost, and resources to analyse the project's prospective results. In most cases, the project estimate is completed by holding estimating workshops with project stakeholders and senior team members who can contribute useful information to the estimation process.

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