Live in beta · 92 tools
92 calculators and free EICR, EIC and MEIWC certificate templates for marine and industrial electrical engineers. Every answer shows its working and names the standard it came from.
Tools
92
Across 16 categories, from cable sizing to CCTV pixel density.
Certificate templates
EIC, EICR, MEIWC, IR test, PAT and more.
Standard
Removes Jolt branding and saves your work. Everything else is free.
On site
Runs in a switchroom, an engine room or a hold. No signal needed.
Every tool names the standard it works to and shows the intermediate steps — derating factors, corrections, limits — so you can defend the number in a review. All of it is free to use and free to download.
Cable sizing, fault levels, volt drop and battery banks, with every derating factor shown rather than folded into the answer.
Templates that fill themselves from the calculation you just ran. Download the PDF free with Jolt branding, or put your own logo on it.
Site paperwork filed against the job rather than scattered across your camera roll and three group chats.
Eight certificate templates to BS 7671:2018+A4, free to fill in and free to download as PDF. No card, no trial, no watermark across the page.
EICR
Sections A–L of the BS 7671 model form, with the schedule of inspection and the generic schedule of circuit details.
Free to download · BS 7671:2018+A4
EIC
For new installations, additions and alterations.
Free to download · BS 7671:2018+A4
MEIWC
For work that does not extend to a new circuit.
Free to download · BS 7671:2018+A4
IR
Circuit-by-circuit insulation resistance.
Free to download · BS 7671 Part 6
SOI
The tick-list of inspected items.
Free to download · BS 7671:2018+A4
SOR
R₁+R₂, Zs, insulation resistance, polarity and RCD operating times.
Free to download · BS 7671:2018+A4
PAT
Asset register with class, test result, next-test date.
Free to download · IET Code of Practice
EX
Hazardous-area equipment inspection.
Free to download · IEC 60079-17
Open a free EICR templateFills itself from the calculation you just ran, and works offline on site.
If yours isn't here, the contact form goes to a working electrical engineer, not a ticket queue.
Everything you need to do the job. All 92 calculators, every certificate template, the reference tables, and the full working behind each result. No card, no expiry, no trial clock.
Yes. All twelve sections of the BS 7671 model form, the schedule of inspection and the schedule of test results, downloadable as a PDF without paying anything.
IEC 60092-352 for marine cable sizing, IEC 60909 for fault levels, IEEE 485 for battery sizing, BS 7671:2018+A4 for inspection and testing.
Jolt shows its working — the derating factors, the corrections, the limit it checked against.
Yes. Install it to your home screen and it runs with no connection.
Add your logo and company details once in your profile.
Your own logo replaces the Jolt mark, and your work saves between sessions.
Everything you need to do the job
No card, no trial clock
Your name on it, and your work kept
Billed monthly · cancel anytime
Prices in GBP, VAT where applicable. Cancel anytime.
Jolt was born out of frustration. As a working electrical engineer I kept reaching for the same calculations, certificates and references every day.
Jakub Burakowski — Founder and Electrical Engineer, Glasgow
Jolt is operated from Glasgow, United Kingdom. For any privacy question, use the contact form.