Free Online Calculators
Finance, math, health, construction, and everyday tools in one searchable catalog.
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Grass Seed Calculator — Lawn Areas, Bags & Cost
Gravel Calculator — Volume, Tons, Bags & Delivery
Grout Calculator — Coverage & Package Purchase Plan
Headphone Power Calculator
IPv4 Subnet Calculator
Insulation Calculator — Packages, Layers & Cost
Knitting Increase & Decrease Calculator
LED Resistor Calculator
Laminate Flooring Calculator — Layout, Cartons & Cost
Linear Regression Calculator
Long Division Calculator
Macrame Cord Calculator — Sample, Cut & Spool Plan
Calculator descriptions
Grass Seed Calculator — Lawn Areas, Bags & Cost
Plan seed for multiple lawn areas using your product label. Combine new lawns and overseeding, subtract existing seed and buy whole bags.
Gravel Calculator — Volume, Tons, Bags & Delivery
Estimate gravel for rectangular, circular or measured areas. Compare cubic yards, tons, bags, supplier order increments and delivery costs.
Grout Calculator — Coverage & Package Purchase Plan
Plan grout for floors, walls and backsplashes. Combine product-specific coverage, keep colours separate, and get whole packages, remainder and an optional cost.
Headphone Power Calculator
Convert headphone sensitivity into required voltage, current and power. Compare headphones and explicit amplifier voltage and current limits.
IPv4 Subnet Calculator
Inspect IPv4 networks and plan aligned, nonoverlapping subnets for different host requirements. See exact address counts, /31 links, /32 routes and remaining CIDR blocks.
Insulation Calculator — Packages, Layers & Cost
Plan batts, rolls or loose-fill bags from product-label coverage. Combine surfaces, keep products separate and build a purchase list with your own quotes.
Knitting Increase & Decrease Calculator
Plan evenly spaced M1, KFB or K2tog in one knit row or round. Follow exact source stitches, step through the row and print your instructions.
LED Resistor Calculator
Choose a standard resistor for small DC LEDs, check a resistor you have and see current, power and wiring for series strings or parallel branches.
Laminate Flooring Calculator — Layout, Cartons & Cost
Plan laminate for multiple rooms. Compare row direction, reuse compatible offcuts and calculate separate carton orders with existing stock and your prices.
Linear Regression Calculator
Fit a line to paired measurements, inspect residuals, compare mean and individual prediction intervals, and explore the influence of one point.
Long Division Calculator
Divide whole numbers and decimals with exact answers and place-value working. Follow the steps or try each quotient digit with immediate feedback.
Macrame Cord Calculator — Sample, Cut & Spool Plan
Plan macrame cord lengths from your own knotted sample. Separate working and filler cords, add cut margin, and see an intact cutting plan for whole spools.
