The free calculators blog.
Practical guides, how-to articles and tips that explain the numbers behind the calculators, from retirement contributions to body composition.
How Much Should I Contribute to My 401(k)?
Most people guess their contribution rate or copy whatever HR suggested at onboarding. Here is how to work out the right number for your own situation.
Latest articles
Fresh from the blog.
How Much Should I Have in Savings?
A clear breakdown of how much to have saved at every stage of life, and what to do if you are behind.
25 Feb 2026 · 6 min readBMI vs Body Fat Percentage: Which One Matters?
BMI is quick and easy but tells only part of the story. We compare both metrics so you know which one to trust.
25 Feb 2026 · 7 min readIRA vs 401(k): The Key Differences
Contribution limits, tax treatment and employer match: how these two retirement accounts differ and which one fits you.
25 Feb 2026 · 7 min readBrowse by topic
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