Guides
How-to guides from TriVisionTech
Practical walkthroughs on the things our apps and free tools help with - images, passwords, accessibility, money and documents. No fluff, and every guide links to a tool you can use right away.
How to Organise a Secret Santa Online: Rules, Budget and a Fair Draw
Run a Secret Santa by link: a fair draw nobody can peek at, a budget that suits everyone, wish lists and a date — for family, friends or the office.
Read the guide →Brazil's 13th Salary in 2026: How to Calculate It, When It Is Paid and the Net Amount
How to work out the full and proportional 13th salary in Brazil, the dates of the two instalments, the INSS and income-tax deductions and worked examples with 2026 figures.
Read the guide →Vacation Pay in Brazil 2026: The One-Third Bonus and Selling 10 Days, Explained
What you get for vacation in Brazil with the constitutional one-third bonus, how selling 10 days (abono pecuniário) works, INSS and income-tax deductions, deadlines and worked examples.
Read the guide →FGTS Birthday Withdrawal (Saque-Aniversário): How Much You Can Take Out and When It Pays Off
The official table of the FGTS birthday withdrawal with examples, the dates to withdraw, what happens if you are dismissed and when switching makes sense.
Read the guide →How to Calculate Percentages: Formulas, Examples and the Most Common Mistakes
The four everyday percentage questions – X% of a number, what percentage one number is of another, increases and discounts, percentage change – with examples and shortcuts.
Read the guide →The Rule of Three: How to Use It for Direct and Inverse Proportions, with Worked Examples
How to set up the rule of three, how to tell direct from inverse proportion, everyday worked examples and how to use it for percentages and conversions.
Read the guide →BMI: How to Calculate Your Body Mass Index and What Each Range Means
The BMI formula with examples, the WHO table for adults, the healthy weight range for your height and the limits of the index.
Read the guide →How to Calculate Severance Pay in Brazil (Rescisão) in 2026: Step by Step
What you are owed for each kind of termination in Brazil, how to work out the balance of salary, notice, the 13th salary, vacation pay, the FGTS fine and deductions – with a full worked example using 2026 figures.
Read the guide →Net Salary in Brazil 2026: How to Calculate INSS and Income Tax (with the New Exemption)
Brazil's 2026 INSS and income-tax tables, the exemption for pay up to R$ 5,000, the simplified deduction and worked examples from gross to net pay.
Read the guide →Simple Interest: Formula, Worked Examples and How It Differs from Compound Interest
The formula I = P × r × t explained with worked examples – interest, final amount, rate, time and principal – and why compound interest grows faster.
Read the guide →Gestational Age: How to Count Pregnancy Weeks and Work Out the Due Date
Why pregnancy is counted from the last period, Naegele's rule for the due date, when an ultrasound changes the dates and the main prenatal milestones.
Read the guide →Overtime and Night-Shift Pay in Brazil (CLT) 2026: How to Calculate
Hourly rate, 50% and 100% premiums, the shorter night hour, the weekly-rest add-on and hour banks — with a worked example under Brazil's CLT.
Read the guide →CDB, Tesouro Selic or LCI/LCA: Which Pays More in Brazil? Tax, FGC and Liquidity
How to really compare CDB, Tesouro Selic and LCI/LCA: the regressive income tax, the exemption, the FGC guarantee, the custody fee, liquidity and the equivalent-CDB formula.
Read the guide →SAC or Price: Which Brazilian Loan Amortisation Is Better? A Worked Example
Fixed payment (Price) or falling payment (SAC)? How each system splits interest and principal, how much you pay in total and when extra payments help most.
Read the guide →Black Friday 2026: How to Tell if a Discount Is Real (and Pay Less)
Five checks before you buy: price history, the final price in the cart, the interest hidden in "interest-free" instalments, scams to avoid and your rights.
Read the guide →Working on Christmas and New Year in Brazil: Holiday Pay (CLT)
Double pay or a day off, Christmas Eve and New Year's Eve, 12x36 shifts, retail and domestic workers — with an example of what reaches the payslip.
Read the guide →Collective Vacation in Brazil (Férias Coletivas): CLT Rules and Pay
At least 10 days, 15 days' notice, pay with the extra third, employees who haven't completed 12 months and selling days — with a worked example.
Read the guide →Brazil's Minimum Wage 2027: Projected Value and Who It Affects
The budget projects R$ 1,741 from January. The formula (INPC + GDP), when the official value comes out and what changes for INSS, MEI and benefits.
Read the guide →13th Salary in Brazil: Pay Off Debt or Invest? Decide with Numbers
Compare your debt's interest with what an investment pays: overdraft, credit card revolving, emergency fund and Tesouro Selic, with worked examples.
Read the guide →Brazil Holidays 2027: Calendar, Long Weekends and Business Days
All national holidays of 2027 with the weekday, the 4-day bridges, business days per month (254 in the year) and the vacation start rule.
Read the guide →INSS for the Self-Employed and MEI in Brazil: How Much to Pay in 2026
20%, 11% or 5%: monthly amounts, the MEI DAS, what each plan gives you, a R$ 3,000 example, payment codes and deadlines.
Read the guide →Unemployment Insurance in Brazil 2026 (Seguro-Desemprego): Who Gets It, How Much and How Many Installments
Who qualifies, the 2026 table (R$ 1,621.00 to R$ 2,518.65), installments by request and time worked, examples, how and when to apply.
Read the guide →Ethanol or Petrol? The 70% Rule for Flex Cars, and When It Is Wrong
Why 70%, the highest ethanol price for each petrol price, how your car’s consumption changes the answer and how much you can save.
Read the guide →Electricity Bill: How Much Each Appliance Uses and How to Work It Out
The sum for each appliance, what a typical Brazilian home spends on the electric shower, air conditioner and fridge, the tariff flags and where to save.
Read the guide →How to Compress a Video for WhatsApp, E-mail or Discord: Size, Length and Resolution
The size limits, the sum behind a video's size, what fits in WhatsApp's 16 MB at each length and why a lower resolution looks sharper.
Read the guide →How to Cut a Video Without Losing Quality (and Why the Cut Can Start a Bit Early)
Copy or re-encode, key frames, marking exact times and turning a horizontal video into a vertical 9:16 for Reels, TikTok and Status.
Read the guide →How to Make a Ringtone from a Song on Android and iPhone
Which part of the song to keep, how long a ringtone can be, and how to set it on Android (MP3) and iPhone (M4A, GarageBand or .m4r).
Read the guide →Video to GIF: How to Make an Animated GIF That Is Not Huge
Why GIFs get so big, the three settings that keep them small (length, width, frames per second), good settings for each use and when an MP4 is better.
Read the guide →Notice Period in Brazil (Aviso Prévio) 2026: How Many Days, Worked or Paid in Lieu
30 days plus 3 per full year, up to 90; 2 hours off a day or 7 straight days; what changes when it is paid in lieu — with a table and a worked example.
Read the guide →Dismissal by Agreement in Brazil (Art. 484-A): What You Get, FGTS and Unemployment Insurance
Half the notice paid in lieu and half the FGTS fine (20%), 80% of the balance withdrawn and no unemployment insurance — compared with dismissal without cause, with an example.
Read the guide →Transport Voucher in Brazil (Vale-Transporte): The 6% Deduction and When to Opt Out
The employee pays up to 6% of the base salary and the employer covers the rest; if fares cost less, only the cost is deducted — with examples and the low-salary case.
Read the guide →Family Allowance in Brazil 2026 (Salário-Família): R$ 67.54 per Child and Who Qualifies
Paid to employees earning up to R$ 1,980.38 a month, per child under 14 or with a disability; documents, who pays and examples — 2026 values from Portaria MPS/MF 13/2026.
Read the guide →Unhealthy Work Allowance in Brazil (Insalubridade) 2026: 10, 20 or 40% of the Minimum Wage
R$ 162.10, R$ 324.20 or R$ 648.40 a month in 2026, by degree; who sets the degree, how it feeds into the 13th salary and vacation, and how it differs from hazard pay.
Read the guide →What a CLT Employee Costs in Brazil in 2026: Charges, Reserves and an Example
From salary to the real cost for the company: FGTS, employer INSS by tax regime, 13th-salary and vacation-third reserves, transport voucher and benefits — with a table for R$ 3,000.
Read the guide →Simples Nacional Fator R: How to Calculate It and Move From Annex V to III
Payroll of 12 months ÷ revenue of 12 months: at 28% or more, a Brazilian service company pays under annex III, not V. Formula, a DAS example and how much pró-labore is missing.
Read the guide →CLT or PJ in Brazil: How to Compare a Job Offer With 2026 Numbers
Add up the whole CLT package (13th salary, vacation third, FGTS, benefits) and see what the PJ invoice must be to match it — an example with a R$ 8,000 salary in the Simples, fator R.
Read the guide →How to Check Colour Contrast for Accessibility (WCAG Explained)
What the AA and AAA contrast levels mean, how the contrast ratio is measured, and how to fix a colour pair that fails – without redesigning everything.
Read the guide →Compound Interest Explained: How Small Monthly Savings Grow
The difference between simple and compound interest, why time matters more than the rate, and how a modest monthly habit turns into a large number.
Read the guide →How to Compress Images Without Losing Quality
A practical guide to shrinking photos for the web and email: resize first, pick the right format, and find the quality sweet spot – without visible loss.
Read the guide →How to Create a Strong Password You Can Actually Remember
Length beats complexity. Here is how to build passwords that are genuinely hard to crack, why a passphrase is easier to live with, and the mistakes to avoid.
Read the guide →How to Scan Documents With Your Phone (and Get a Clean PDF)
Get flat, readable, properly cropped scans from a phone camera: lighting, background, colour mode, multi-page PDFs, and making the text searchable.
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