Blog
Guides & tutorials
Practical guides on QR codes, developer tools, networking, and getting more done — from the OhoTool team.
What Is the Pomodoro Technique?
The Pomodoro Technique explained — how the 25/5 focus method works, why it helps you concentrate, and a free online timer to run it. Plus tips that actually stick.
How to Humanize AI Text
AI drafts often read stiff and repetitive. Here's how to make AI-generated text sound natural and human — the tells to fix, and a free tool that does it for you.
How to Come Up With a Business Name
Stuck naming your business? A practical process for brainstorming brandable names — plus a free AI generator to spark ideas and what to check before you commit.
How to Make a Free Invoice (Fast)
Create a professional invoice PDF for free in minutes — no template hunting, no sign-up. What to include on an invoice and how to generate one in your browser.
Online Notepad: Free Notes That Autosave
A free online notepad that saves as you type — no sign-up, nothing uploaded. How to jot notes in your browser, keep them across visits, and export them.
How to Convert HTML to PDF (Keep the Layout)
Turn an HTML file into a clean, shareable PDF with the layout preserved — great for invoices, reports, and templates. Here is how, and when to use URL to PDF instead.
How to Convert a PDF to PowerPoint (Editable Slides)
Turn a PDF back into an editable PowerPoint deck — each page becomes a slide you can reuse and present. Here is how, plus what converts cleanly and what needs tidying.
How to Convert CSV to Excel (Keep Your Columns)
Turn a messy CSV into a proper Excel spreadsheet with the data split into real columns — ready to sort, filter, and format. Here is the reliable way to do it.
How to Remove Background Noise From Audio (Free Online)
Clean up a noisy recording — cut hiss, hum, and fan noise, and make a quiet voice clear and even. Free, in your browser, with no upload and no software.
How to Convert Audio to MP3 (Free, in Your Browser)
Turn WAV, M4A, or any audio file into a universal MP3 — free, fast, and private. No upload, no software, no watermark. Plus when to use WAV or M4A instead.
How to Crop an Image Online (Free, No Upload)
Crop a photo to the exact size or shape you need — a square for Instagram, 16:9 for a thumbnail, or a circle for an avatar. Free and entirely in your browser.
How to Password-Protect a File You Share
Share a file so only the person with the password can open it. A simple, private way to password-protect files you send online — no software to install.
How to Send Large Files for Free (Securely)
The easiest way to send a large file to someone — free, no account, and end-to-end encrypted. Plus what to do when a file is too big to email.
How to Convert Images to WebP (Smaller, Faster Pages)
Convert JPG and PNG images to WebP for much smaller files and faster page loads. What WebP is, when to use it, and how to convert in your browser.
How to Compress an Image Without Losing Quality
Shrink a JPG or PNG so it fits an email limit or loads fast on your site — without it turning into a blurry mess. What actually reduces file size, and how.
How to Convert PowerPoint to PDF (Slides & Handouts)
Turn a PowerPoint presentation (.pptx or .ppt) into a PDF so your slides look identical everywhere and make clean, printable handouts.
How to Convert Excel to PDF (and Keep It on One Page)
Convert an Excel spreadsheet (.xlsx or .xls) to a clean PDF for sharing or printing — with tips to stop your columns spilling onto extra pages.
How to Convert Word to PDF (Without Losing Formatting)
Convert a Word document (.doc or .docx) into a clean, shareable PDF that keeps your fonts, images, and layout exactly as designed. A quick step-by-step.
How to Convert HEIC to JPG (iPhone Photos)
iPhone photos save as HEIC, which many apps can't open. Here's how to convert HEIC to JPG so your photos work everywhere.
How to Save a Web Page as a PDF
Archive any web page as a clean PDF — great for articles, receipts, and documentation. A quick guide to converting a URL to PDF.
How to Compress a PDF to Reduce File Size
Shrink a large PDF so it's easy to email and upload. A practical guide to reducing PDF file size without losing readability.
How to Extract Text From an Image (OCR)
Pull editable text out of a photo, screenshot, or scanned document using OCR. A quick guide to turning images into copyable text.
How to Convert a PDF to Word (Editable DOCX)
Convert a PDF into an editable Word document while keeping the layout. A quick guide to turning PDFs back into editable .docx files.
How to Convert and Resize Images in Bulk
Batch-convert and resize many images at once — to WebP, JPG, or PNG — for free in your browser, then download them all as a ZIP.
How to Convert a PDF to JPG or PNG (Free, In Your Browser)
Turn PDF pages into JPG or PNG images for free — privately in your browser. Learn when to use JPG vs PNG and how to keep the quality sharp.
How to Merge PDF Files for Free (Without Uploading Them)
Combine multiple PDFs into one file for free — right in your browser, with nothing uploaded to a server. A quick, private, step-by-step guide.
How to Decode a JWT (JSON Web Token) — Safely
Understand what's inside a JSON Web Token, how to decode its header and payload, and why decoding is not the same as verifying.
How to Add a Logo to a QR Code (Without Breaking It)
Add your logo and brand colors to a QR code so it still scans reliably. Learn about error correction, contrast, sizing, and testing.
How to Create a Strong Password in 2026
What actually makes a password strong, the mistakes to avoid, and how to generate and manage passwords you can trust — a practical 2026 guide.
What Is Base64 Encoding? A Simple Guide with Examples
Base64 explained in plain English: what it is, how it works, when to use it, and why it isn't encryption — with hands-on examples.
How to Format & Fix JSON (Common Errors)
Learn how to format and validate JSON, minify it for production, and fix the most common JSON syntax errors — trailing commas, single quotes, and more.
15 Free Developer Tools That Run Entirely in Your Browser
A roundup of fast, private developer tools that work 100% in your browser — no uploads, no sign-up. JSON, Base64, JWT, regex, hashing, and more.
CIDR & Subnet Cheat Sheet: /24, /29, /30 Explained
A plain-English CIDR cheat sheet — what each prefix (/24, /29, /30, /32) means, its subnet mask, and how many hosts it holds, with a free calculator.
How to Make a Dynamic QR Code for a Restaurant Menu (Free)
Create a QR code menu you can update anytime without reprinting — and see how many people scan it. A step-by-step guide for restaurants and cafés.