iziznkit
Free right now · EN / RU

Handy tools, right in your browser.

Calculators, converters, document generators and developer utilities — no sign-up, no install. Fill a form, get the result, done. Everything is free right now.

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  • 12 currencies
30
Tools, and growing
EN · RU
Fully bilingual
Free
Every tool, right now
~1 min
To your first PDF

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Documents

Generate clean, ready-to-send business documents.

Developer tools

Fast, no-login utilities for everyday coding.

JSON formatterPopular

Format, validate and minify JSON in your browser.

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Base64 encoder / decoder

Encode or decode Base64 text, UTF-8 safe.

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JWT decoder

Decode a JWT's header and payload in your browser.

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Regex tester

Test regular expressions with live match highlighting.

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URL encoder / decoder

Percent-encode or decode URLs and query strings.

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UUID generator

Generate random UUID v4 identifiers in bulk.

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Hash generator (SHA)

SHA-1, SHA-256, SHA-384 and SHA-512 of any text.

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Unix timestamp converter

Convert Unix timestamps to dates and back.

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Color converter

Convert colors between HEX, RGB and HSL.

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Text diff / compare

Compare two texts and highlight what changed, line by line.

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Cron expression parser

Explain a cron schedule in plain English and see the next run times.

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Case converter

UPPERCASE, lowercase, Title, camelCase, snake_case and more.

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Lorem ipsum generator

Placeholder text — paragraphs, sentences or words.

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CSS gradient generator

Build a gradient and copy the CSS.

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JSON to CSV converter

Convert JSON to CSV and CSV to JSON in your browser.

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JSON to TypeScript & Go

Generate TypeScript interfaces or Go structs from JSON.

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YAML ↔ JSON converter

Convert YAML to JSON and JSON to YAML in your browser.

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Markdown to HTML preview

Write Markdown, see the HTML preview and copy the source.

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Image to Base64

Turn an image into a Base64 data URI — in your browser.

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SQL formatter & beautifier

Format and beautify SQL for 10+ dialects — in your browser.

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Image to WebP converter & compressor

Convert images to WebP, JPEG or PNG and shrink the file — in your browser.

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chmod calculator

Build Unix file permissions — octal, symbolic and a ready chmod command.

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XML formatter

Beautify or minify XML and catch parse errors in your browser.

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Minify & beautify (HTML/CSS/JS)

Beautify or minify HTML, CSS and JavaScript — locally, with size stats.

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Cron expression builder

Build a cron schedule from presets or fields, with a plain-language summary.

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Color palette & shades generator

Generate tints, shades and color harmonies from any base color.

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One tool, six designs

Switch the look in a click — your download always matches.

INVOICE
Classic$1,260
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Modern$1,260
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Minimal$1,260
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Rose$1,260
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Amber$1,260
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Royal$1,260

Guides

Short, practical how-tos — with a free tool at the end of each.

All guides →
How to make an invoice (free template)A simple guide to creating a professional invoice — what to include, how to number it, and how to get paid faster. Free invoice generator included.Read →How to write a property inspection report (move-in / move-out)Record a rental's condition room by room, with photos and dates, so the deposit is split fairly. What to include, how to word defects, and a free template.Read →Mutual vs unilateral NDA: what's the difference?Mutual (two-way) vs unilateral (one-way) NDA — the real differences, when to use each, mNDA vs NDA, and a free generator to make one in a minute.Read →What is a unilateral NDA?A unilateral (one-way) NDA explained — what it is, how it works, when to use one, whether it's enforceable, and how to create one free.Read →What is a mutual NDA?A mutual (bilateral) NDA explained — what it is, when both sides share, how it differs from a one-way NDA, and how to create one free.Read →How to create a strong passwordWhat actually makes a password strong — length, randomness and entropy — plus the common mistakes to avoid and a free generator.Read →Freelance and self-employed tax, explainedHow freelancers and the self-employed estimate tax and take-home pay — what's taxed, common regimes, and a free calculator.Read →How to write a quote clients say yes toWhat a good quote (estimate) includes, how to price and present it, and how to win the work — plus a free quote generator.Read →What is a JWT? A plain-English guideWhat a JSON Web Token is, how its three parts work, when to use one, and a free decoder to inspect any token.Read →What is hashing? SHA-256 in plain EnglishHow a hash function works — one-way, fixed-length and deterministic — what SHA-256 is for, and a free tool to hash any text.Read →What is a cron expression? A plain-English guideHow the five cron fields work — with ranges, lists and steps — how to read a schedule, and a free parser that shows the next run times.Read →What is a UTM parameter? A marketer's guideWhat UTM parameters are, what each of the five does, naming conventions that keep reports clean, and a free UTM link builder.Read →What is compound interest? A plain-English guideHow compound interest works, why it beats simple interest, the formula, and how compounding frequency and regular deposits grow your money — with a free calculator.Read →How to calculate rental yield (gross vs net)What rental yield is, how to work out gross and net yield, what counts as a good yield, and a free calculator to check any property.Read →What is unit economics? A seller's guideUnit economics explained for marketplace sellers — profit per unit, margin, break-even price, and a free calculator to model it.Read →Marketplace unit economics: Ozon, Wildberries & Yandex MarketHow to calculate unit economics for a marketplace seller — commission, fulfillment, returns and promo, with a worked example and a free calculator.Read →FBO vs FBS: which marketplace fulfillment model costs you lessFBO, FBS and realFBS compared for Ozon, Wildberries and Yandex Market sellers — who stores the stock, which fees each model charges, and how to pick by the numbers.Read →How to calculate VAT (add and remove)How VAT works, how to add VAT to a net price and remove it from a gross one, the formulas, and a free VAT calculator.Read →Is margin calculated with or without VAT?Margin is calculated without VAT, not with it. See when the gross shortcut is safe, when it fakes points of margin, plus a free VAT-stripping calculator.Read →How to set your hourly rate as a freelancerWork out a freelance hourly rate from the income you want to keep — the formula, realistic billable hours, tax and expenses, and when to raise it.Read →Marketplace seller taxes in 2026: УСН, АУСН or НПДWhich tax regime a Russian marketplace seller should choose in 2026 — УСН, АУСН or НПД. Rates, limits, the 2026 VAT change and the mistakes that cost money. Free calculator included.Read →

Built to be trusted

Small tools, done properly — private, polished, and fairly priced.

01

Private by default

Your data stays in your browser. Nothing is uploaded until you generate a file.

02

Polished, ready to send

Clean, branded PDFs that look professional to your clients — not a spreadsheet export.

03

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