Terms of Use

Last updated: 3 October 2026.

What you are getting

ToolboxCalc provides quantity estimates and reference calculations for building, electrical and garden work. Use of the site is free and requires no account.

Estimates are estimates

The figures here are based on the values you enter and on typical published figures. They are not:

• structural or civil engineering advice, or a construction bid;
• agronomic advice or a substitute for a soil test;
• an electrical design, an inspection, or a code compliance determination;
• a substitute for the instructions and label on the product you actually buy.

Material densities vary with source, moisture and compaction. Bag yields vary between mixes. Seeding rates and fertilizer analyses vary by product and region. Verify against your supplier, the label and your local building department before ordering, building or applying.

Electrical work

Electrical work is dangerous and regulated. Incorrect work causes electrocution and fire. The electrical calculators do not apply ambient temperature correction, conductor bundling adjustment, motor circuit rules, equipment grounding conductor sizing, or local amendments — any of which can require a larger conductor or raceway. The NEC edition your jurisdiction has adopted governs your work, and where it differs from anything here, it wins. Most jurisdictions require permits and inspection, and many restrict who may do the work; nothing on this site authorises you to carry it out.

Chemicals and safety

Fertilizer and lawn products are regulated, and the label carries legally binding application instructions. Where a label rate differs from a figure on this site, follow the label.

Limitation of liability

The site is provided as is, without warranty of any kind. To the fullest extent permitted by law, the operator accepts no liability for any loss, damage, injury or death arising from reliance on this material, including over-ordering, under-ordering, plant loss, or work that does not meet local requirements.

Acceptable use

Do not attempt to disrupt the site or place unreasonable automated load on it. The content and calculators are the operator’s work; you are welcome to use the results for your own projects and to link here, but not to republish the content wholesale.

Changes

These terms may be updated, and the current version is always the one on this page.