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    The rules behind our calculators, in plain English, with worked examples and links to the official sources.

    Gulf jobs

    How Qatar end-of-service gratuity is calculatedThe 3-week rule, which salary counts, part years and worked examples under Qatar Labour Law No. 14 of 2004.UAE gratuity rules explainedHow end-of-service pay works in the UAE private sector: 21 and 30 days per year, the 2-year cap, part years and what salary counts.Saudi end-of-service award explainedHalf a month per year for the first 5 years, a full month after that, and the resignation reductions in Saudi Labour Law.Kuwait end-of-service indemnity explainedHow indemnity works under Kuwait Labour Law No. 6 of 2010: 15 and 26 days, the 1.5-year cap and resignation rules.Oman end-of-service gratuity under the new labour lawWhat changed with Royal Decree 53/2023, who gets gratuity, how much and how leave and overtime are paid.Bahrain end-of-service indemnity explainedHalf a month a year for 3 years, a month after: how Bahrain end of service works, who pays since the SIO scheme began in March 2024 and what resigning changes.End-of-service gratuity in the Gulf: all six countries comparedQatar, UAE, Saudi Arabia, Kuwait, Oman and Bahrain side by side: rates, salary used, caps, resignation cuts and who pays, in months of pay.UAE final settlement explained: what you're owed when you leaveLast salary, gratuity, unused leave on basic pay, notice pay, deductions and the 14-day deadline, with full worked UAE settlements.Annual leave and leave salary in Qatar explained21 days a year, 28 from 5 years, leave paid on basic ÷ 30, carrying leave over and unused leave in your final settlement under Qatar Labour Law.Overtime pay in the Gulf: rules for all six countriesOvertime rates, night and rest-day pay, Ramadan hours, which wage counts and daily limits in the UAE, Saudi, Qatar, Kuwait, Oman and Bahrain.

    Health

    BMI explained: how it's calculated, what the ranges meanThe BMI formula in kg and lb, WHO ranges, the lower NICE cut-offs for some backgrounds, healthy weight for your height, waist-to-height ratio and limits.How many calories do you need? BMR and TDEE explainedBMR vs TDEE, the Mifflin–St Jeor and Katch–McArdle equations, activity factors, why estimates can be 10% off, and gentle deficits.How your pregnancy due date is worked outNaegele's rule, cycle length, conception and IVF dates, when a scan changes your due date, trimesters and why few babies arrive on the day.

    AI & apps

    LLM API costs explained: tokens, caching and batchWhat a token is, why output costs more, prompt caching and batch discounts, context windows and how to estimate a monthly AI API bill.How much GPU memory do you need to run an LLM?Weights, quantisation (FP16 to Q4_K_M), KV cache, MoE, Mac shared memory, fine-tuning and tokens per second, with VRAM tables and worked examples.

    Money

    India income tax: new vs old regime explained (FY 2026-27)New and old regime slabs, the ₹12 lakh rebate, cess, surcharge and how much in deductions the old regime needs to win, with worked examples.India GST explained: rates after the 2025 reformThe 5%, 18% and 40% slabs since September 2025, adding and removing GST, CGST/SGST vs IGST, discounts, multi-item invoices and input tax credit.How EMI is calculated: formula, interest and prepaymentThe EMI formula step by step, why early EMIs are mostly interest, flat vs reducing rates, tenure vs total interest, and reduce EMI or tenure.SIP returns explained: how a monthly investment growsHow SIP maturity is worked out, why compounding speeds up over time, step-up SIPs, SIP vs lump sum, inflation and India tax, with examples.Compound interest explained, with the rule of 72Simple vs compound interest, the formula, monthly vs daily compounding, APY, regular savings, the rule of 72, tax and inflation, with worked examples.

    Aviation

    EASA flight duty period limits (ORO.FTL) explainedMax FDP tables, acclimatisation, WOCL, extensions, in-flight rest, split duty, rest and cumulative limits under EASA FTL, in plain English.DGCA flight duty time limits (FDTL) explainedMax FDP and flight time by landings, night duty, rest, weekly rest, cumulative and augmented crew limits under DGCA CAR 7-J-III (2024).How to calculate crosswind and headwind componentsThe sine and cosine formulas, the clock rule, gusts, true vs magnetic METAR winds, tailwind and picking the best runway, with worked examples.Density altitude explained: how to calculate it and why it mattersPressure altitude, ISA temperature, the exact formula and the 120 ft rule, humidity, and what hot-and-high air does to take-off and climb.Aircraft weight and balance explained: CG and the envelopeWeight, arm and moment, CG = total moment ÷ total weight, the CG envelope, fuel burn and landing CG, %MAC and fixing an out-of-limits load.FAA Part 117 flight duty limits explainedTables A, B and C, acclimatisation, rest, cumulative limits and extensions for US airline pilots, in plain English.Cold temperature altimeter correction explainedWhy altimeters over-read in cold air, the ICAO formula and table, the 4% rule and FAA Cold Temperature Airports.FAA medical expiry and pilot currency explainedWhen your first, second or third class medical expires, BasicMed, the flight review and the 90-day and instrument currency rules.