Blog
Guides, tutorials and how-tos from the MoreFreeTools team. Learn how to get more done with free online tools.
How Barcodes Encode Data: From Grocery Store Stripes to QR Codes
Learn how barcodes actually encode data using binary patterns, check digits, and error correction. Covers EAN-13, UPC-A, Code 128, Code 39, and QR codes.
How PDF Files Actually Work: The Format That Changed Document Sharing Forever
Discover the technical internals of the PDF format: its structure, object model, fonts, xref table, and why some PDFs are unsearchable. 900+ words.
How to Calculate Your Calorie Needs: The TDEE Formula Explained
Learn the science behind TDEE and the Mifflin-St Jeor formula. Discover how BMR, activity multipliers, and adaptive thermogenesis affect your daily calorie needs.
How to Split a Bill Fairly: The Math and Psychology Behind Restaurant Checks
Learn how to split a bill fairly using real math, psychology research, and worked examples. Equal vs. proportional splits, tipping formulas, and more.
White Noise, Pink Noise, Brown Noise: The Neuroscience of Background Sound for Focus and Sleep
Discover the science behind white noise, pink noise, and brown noise. Learn which noise color boosts focus, improves sleep, and why your brain responds differently to each.
How Compound Interest Actually Works: The Math That Explains Why Starting Early Beats Contributing More
Learn how compound interest works with real formulas, the Rule of 72, and a mathematical proof that starting 10 years earlier beats contributing 3x more money over 30 years.
How Much to Feed a Dog (or Cat): The RER Formula Vets Actually Use
Learn how much to feed a dog or cat using the RER formula that veterinary nutritionists rely on, not the bag guidelines that are often 20-30% too high.
How QR Codes Work: Error Correction Explained
Discover how QR codes work under the hood, why Reed-Solomon error correction lets you add a logo to a QR code and still scan it, and how capacity, masking, and version affect every scan.
SIDS Risk Factors: What the Data Actually Shows
A data-driven epidemiological analysis of SIDS risk factors, covering the Triple Risk Model, modifiable and non-modifiable risks, AAP 2022 guidelines, and the serotonin hypothesis.
What a Readability Score Actually Measures (And Where It Breaks Down)
A readability score is more than a writing grade. Learn how the Flesch-Kincaid scale, Gunning Fog, and SMOG Index work, what grade level to target, and how to improve readability without dumbing down your content.
Why 1 Dog Year Is Not 7 Human Years: The Real Science of Dog Age
The '1 dog year equals 7 human years' rule is mathematically wrong and biologically misleading. A 2019 UC San Diego study revealed the true formula for converting dog years to human years, and the answer is logarithmic.
The 21-Day Habit Myth: What the Science Actually Says About How Long Habits Take
The '21 days to build a habit' claim comes from a 1960 plastic surgeon's personal observation, not a study. The only real research on the topic found a range of 18 to 254 days. Here is what actually determines how fast a habit forms, and how to use that data to your advantage.
How to Create a Strong Password: The Math Most Security Guides Skip
Most password advice is outdated and counterproductive. Here is the actual mathematics of password entropy, real crack-time data from GPU benchmarks, and what NIST guidelines actually say in 2026.
How to Make a Gantt Chart in 5 Steps (Free, No Software Needed)
Henry Gantt invented his chart during WWI military production planning. Today, PMI data shows organizations using visual timeline tools waste 28 times less money. Here is a practical 5-step framework for building a Gantt chart from scratch, the critical path concept explained simply, and the most common mistakes that kill projects.
The 90-Minute Sleep Cycle: Why 7.5 Hours Often Beats 8 (And the Math Behind It)
Waking up mid-cycle triggers sleep inertia that can fog your mind for an hour. Here is the ultradian rhythm science, the chronotype data from Matthew Walker's research, and a simple formula to calculate the exact bedtime for your wake-up time.
Why BMI Misleads Millions: The Hidden Flaws Behind a 190-Year-Old Formula
BMI was invented in 1832 for population statistics, not medical diagnosis. Here is what a 2016 UCLA study found, why the military abandoned it, and the three metrics that actually predict your health risk.
Zero-Based Budget vs. 50/30/20: Which Method Actually Builds Wealth (And Which One Is Outdated)
The 50/30/20 rule was calibrated for 2005 American housing costs. Here is a data-backed comparison of the three main budgeting frameworks, the behavioral economics research behind why each one works or fails, and a decision guide for your income type.