ToolsGuru

Guides

Original, example-led writing from ToolsGuru — not scraped tool roundups. Each guide walks a specific job and names the limits of a browser tab.

These pages exist because a grid of 81 tools is not enough publisher content on its own. Reviewers (and people) can tell when every page is the same privacy paragraph with the product name swapped. The guides below are written around jobs we actually modelled: a wedding album a print shop could not open, a fee proposal that had to stay off third-party disks, a firmware checksum that is not a password.

If you only need the tool, skip to the related links at the bottom of each article. If you need to know whether your file leaves the machine, start with the methodology guide and confirm it in your own Network panel.

Methodology

How ToolsGuru keeps files on your device (and how to check)

A practical explanation of client-side processing on ToolsGuru: File APIs, Canvas, Web Crypto, pdf-lib, what still goes over the network, and how to verify it in DevTools.

11 min readRead guide

File conversion

Convert iPhone HEIC photos without uploading them

A worked walkthrough: 184 wedding HEIC files from an iPhone 15 that a Kent print shop’s Windows PC could not open — converted to JPG in the browser, with quality and metadata notes.

9 min readRead guide

PDF tools

Merge and split PDFs on your device — a fee-proposal packet

How a freelance architect combined a 3-page fee proposal with a 12-page drawing register, then split a 5 MB portal-sized extract, all in the browser with pdf-lib.

10 min readRead guide

Developer tools

Hashes, UUIDs, and passwords are three different jobs

A firmware checksum, a SQLite shift ID, and a registrar password — why SHA-256, UUID v4, and a password generator are not interchangeable, with examples you can reproduce in the browser.

10 min readRead guide

Study skills

Hitting a university word count without padding or panic

A 2,500-word UK history essay on the 1832 Reform Act: what to paste into a word counter, how footnotes and bibliographies are treated, and why readability scores are not a predicted mark.

9 min readRead guide

Images for the web

When to use WebP, AVIF, or JPG — 24 coffee-bag photos

An independent roaster’s 24 SKU photos: WebP for Shopify, JPG for a printed catalogue, why AVIF is not always the shop’s friend, and how to convert without uploading the product shoot.

8 min readRead guide