FastTool Answer Engine Task OS Workflow Studio Task Library Tool Finder

BUILT FOR 2026 50 reviewed tools guided workflows 0 signups browser-first tools

Ask a Browser Task. Get the Reviewed Tool Route.

FastTool is an answer engine for real utility work: clean JSON, prepare PDFs, optimize images, check writing, choose readable colors, run practical calculators, and inspect technical values with safe samples and output checks.

Try now: Word counter JSON formatter Password generator Image compressor PDF merger HTML to PDF BMI calculator Regex tester
Open Answer Engine Build a task plan Open Workflow Studio Browse Task Library Find the right tool Browse 50 Reviewed Tools

Clear privacy boundaries Local processing where supported 21 languages Dark mode

Popular right now

Reviewed tools 50
Categories 17
Top category Developer

YOUR FASTTOOL WORKSPACE

Continue, decide, or verify quality

FastTool now behaves like a repeat-use workspace, not a one-off directory. Recent tools and saved tools stay in this browser only.

DAILY TOOL DESK

Come back to the same useful workflows

FastTool is organized around repeat tasks: answer routes, publish checks, API debugging, document cleanup, image prep, text review, and everyday calculators.

Answer Engine

Ask the job and get a route

Type a practical question like "compress a PDF before email" or "fix invalid JSON" and get a reviewed path with sample input, expected output, and checks.

Task OS

Turn a problem into a verified plan

Describe the job and get a tool chain, safe test sample, expected output, verification checklist, and caution notes before you start.

Start here

Continue a real workflow

Use ordered steps, local progress, output checks, and exportable checklists for API data, PDFs, images, writing, design, calculations, and security tasks.

Choose

Find the right starting tool

Not sure where to begin? Pick the task first, then jump into reviewed tool pages with clear trust checks.

Debug

Fix JSON and API payloads

Format, validate, compare, encode, decode, and convert structured data without leaving the browser.

Images

Compress an image for upload

Reduce file size locally, then resize or convert the image when a form, store, or document needs a specific format.

Documents

Clean up a PDF workflow

Use ordered PDF tools for conversion, extraction, compression, merging, splitting, and browser-first document fixes.

Writing

Check text before sending

Count words, characters, reading time, and structure before publishing copy, emails, posts, or documentation.

Finance

Run a practical money check

Compare loans, interest, savings, investment growth, tax assumptions, and everyday finance decisions with transparent calculators.

QUALITY GATE

Reviewed tools first, weaker pages held back

Read the standards →

FastTool is moving from catalog quantity to task quality. The homepage promotes reviewed pages with realistic inputs, expected outputs, limitation notes, and review evidence first. Broader direct-use utilities remain available by URL, while generic pages stay out of search until they are rewritten with stronger examples and clearer user value.

Reviewed now

50 high-value tool pages

JSON, password, PDF, image, calculator, converter, and developer tools now include field-tested examples and practical trust notes.

Search quality

Noindex for unfinished pages

Utility pages that are useful but not yet differentiated stay available from the app, but they are removed from sitemap and search eligibility until rewritten.

User experience

Promote pages that solve the task

The goal is fewer weak landing pages and more paths that give visitors a clear input, a useful output, and a reason to come back.

TRENDING TOOLS

12 reviewed standouts

A curated mix of reviewed document, developer, image, writing, design, and calculator tools.

WritingWord & Character CounterWritingCount words, characters, lines, and estimated reading time. DeveloperJSON Formatter & ValidatorDeveloperFormat, minify, and validate JSON with syntax highlighting, tree view, JSON path on click, error detection with line/column, stats, and file upload/download. ImageImage CompressorImageCompress images in your browser, reduce file size while keeping quality. DocumentPDF MergerDocumentMerge multiple PDF files into one document directly in your browser. Drag to reorder, see page counts, and download the merged PDF instantly. browser-based — your standard processing stays in your browser. MathPercentage CalculatorMathCalculate percentages with 4 modes: X% of Y, what percent X is of Y, percentage change, and markup/discount. Real-time results with visual bar and stat cards. FinanceCompound Interest CalculatorFinanceCalculate compound interest with interactive growth chart, year-by-year table, and contribution breakdown. DesignColor PickerDesignPick colors with EyeDropper, get HEX/RGB/HSL/CMYK/HWB values, explore harmonies and gradients. SecuritySecure Password GeneratorSecurityGenerate strong passwords with custom length and character sets. DocumentHTML to PDF ConverterDocumentConvert raw HTML or local .html files to PDF with preview, CSS controls, and browser-only export. DeveloperRegex TesterDeveloperTest regex patterns with real-time match highlighting, capture groups, replace mode, and a built-in cheatsheet. HealthBMI CalculatorHealthCalculate BMI with visual gauge, color-coded results, age/gender context, and BMI reference chart. DeveloperUUID GeneratorDeveloperGenerate UUID v4 with bulk generation (1-100), format options (standard, uppercase, no dashes, Base64), UUID validator with version detection, click-to-copy, download as TXT, and generation history.

WHY FASTTOOL

What makes us different

Most online tool sites are ad-walls with a form on top. We built the opposite.

SMART STACKS

Turn a task into a tool workflow

Pick the job, then jump through the strongest tools in the right order.

BEST START

Type a task or choose a stack

Search for a job like compress image, SEO article, AI cost, or PDF merge.

  1. Image CompressorReduce file size before publishing.
  2. PDF MergerCombine documents before sharing or archiving.
  3. JSON FormatterClean and inspect structured data.

How it works

1

Pick a tool

Browse the 50 reviewed tools first; direct-use tools stay available by URL while weaker pages are rewritten.

2

Use it instantly

Reviewed tools are designed for fast browser-based work with no account required; some pages may load third-party resources for ads, analytics, fonts, or libraries as disclosed.

3

Get results

Copy, download, or share your results. Standard tool input stays in your browser where local processing is supported.

/ to search

BROWSE BY CATEGORY

Featured categories

Developer dataJSON, CSV, YAML, JWT DocumentsPDF merge, split, compress ImagesCompress, resize, convert WritingCount, read, prepare DesignContrast, palette, CSS Finance estimatesLoan and interest checks CalculationsPercent, unit, science Security valuesPasswords, UUIDs, hashes Health estimatesBMI with clear limits FocusPomodoro workflow Not sure?Ask the task first

START WITH A WORKFLOW

Reviewed workflows, not random browsing

These paths use reviewed tools only, so the homepage points users toward pages with stronger examples, limitations, and working browser output.

TASK WORKFLOWS

Start where search intent starts

All task routes →

Not sure which workflow matches the job? Use the Tool Finder to jump from a real task to the strongest public tool page.

PDF WORKFLOW

Prepare a PDF Packet

Turn messy document work into a checkable PDF route with sample input and output checks.

Open task route →

DATA WORKFLOW

Fix Invalid JSON

Move structured data from broken paste to clean, validated, copy-ready output.

Open task route →

IMAGE WORKFLOW

Make an Image Smaller

Prepare lighter, cleaner images for websites, documents, stores, and social posts.

Open task route →

PUBLISH WORKFLOW

Check a Page Before Publishing

Run a practical page-quality pass before publishing or updating a page.

Open task route →

DEVELOPER WORKFLOW

Clean Code Snippets

Format or minify snippets with a clear verification checklist.

Open task route →

FINANCE WORKFLOW

Compare Finance Estimates

Model common money decisions with transparent assumptions and clear limits.

Open task route →
50Reviewed tools
17Categories
$0Forever Free
LocalProcessing

TRENDING THIS WEEK

Reviewed tools worth trying first

JSON Formatter & ValidatorPopular

Developer

Format, minify, and validate JSON with syntax highlighting, tree view, JSON path on click, error detection with line/column, stats, and file upload/download.

Try it

Image CompressorPopular

Image

Compress images in your browser, reduce file size while keeping quality.

Try it

PDF MergerPopular

Document

Merge multiple PDF files into one document directly in your browser. Drag to reorder, see page counts, and download the merged PDF instantly. browser-based — your standard processing stays in your browser.

Try it

HTML to PDF ConverterNew

Document

Convert raw HTML or local .html files to PDF with preview, CSS controls, and browser-only export.

Try it

Regex TesterPopular

Developer

Test regex patterns with real-time match highlighting, capture groups, replace mode, and a built-in cheatsheet.

Try it

BMI CalculatorPopular

Health

Calculate BMI with visual gauge, color-coded results, age/gender context, and BMI reference chart.

Try it

Age Calculator

Lifestyle

Calculate your exact age in years, months, days, total weeks, hours, and minutes. See your zodiac sign, Chinese zodiac, generation label, birthday weekday, and countdown to your next birthday.

Open reviewed tool

Aspect Ratio Calculator

Design

Calculate and convert aspect ratios for images, video, and responsive design. Enter width and height to find the ratio, or enter a ratio plus one dimension to calculate the other. Lock ratio toggle, common presets (16:9, 4:3, 1:1, 21:9, 9:16), visual preview rectangle, and platform-specific size recommendations for YouTube, Instagram, Twitter, Facebook, and LinkedIn.

Open reviewed tool

Base64 Encode/Decode

Developer

Encode and decode Base64 with text mode, file mode, image-to-Base64 data URI, Base64-to-image preview, URL-safe variant toggle, live conversion, character count, and download support.

Open reviewed tool

Case Converter

Writing

Convert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, aLtErNaTiNg CaSe, and Inverse Case with real-time preview and character stats.

Open reviewed tool

WCAG Contrast Checker

Design

Advanced WCAG 2.1 contrast checker with AA/AAA pass/fail badges, color blindness simulation, auto-fix suggestions, live text preview, and random accessible palette generator.

Open reviewed tool

Color Palette Generator

Design

Generate beautiful color palettes from any base color. Choose from complementary, analogous, triadic, split-complementary, tetradic, and monochromatic harmonies. Export as CSS variables, Tailwind config, or SCSS. Built-in contrast checker with WCAG AA/AAA compliance.

Open reviewed tool

CSS Gradient Generator

Design

Create stunning CSS gradients with linear, radial, and conic types. Angle slider, up to 8 color stops with position control, 20 beautiful presets, live preview, full-screen mode, and one-click CSS copy with vendor prefixes.

Open reviewed tool

CSV to JSON Converter

Data

Convert CSV to JSON or JSON to CSV with auto-delimiter detection. Upload .csv files or paste data. Preview table, toggle header row, handle quoted fields and edge cases. Download or copy output.

Open reviewed tool

JWT Decoder

Security

Decode and inspect JWT tokens with color-coded header, payload, and signature sections. Check expiry status, verify HMAC-SHA256 signatures, and explore common JWT claims.

Open reviewed tool

Loan Calculator

Finance

Calculate loan payments with SVG balance chart, amortization table, extra payment savings, and payoff date for monthly, biweekly, or weekly schedules.

Open reviewed tool

PDF Merger

Document

Merge multiple PDF files into one document directly in your browser. Drag to reorder, see page counts, and download the merged PDF instantly. browser-based — your standard processing stays in your browser.

Open reviewed tool

PDF Splitter

Document

Split PDF files into individual pages or custom page ranges directly in your browser. Extract specific pages, split every N pages, or split into single pages. browser-based — your standard processing stays in your browser.

Open reviewed tool

Percentage Calculator

Math

Calculate percentages with 4 modes: X% of Y, what percent X is of Y, percentage change, and markup/discount. Real-time results with visual bar and stat cards.

Open reviewed tool

Pomodoro Timer

Productivity

Focus timer with presets, streak tracking, daily stats, keyboard shortcuts, browser notifications, and multiple sound options.

Open reviewed tool

QR Code Generator

Data

Generate QR codes for URLs, text, WiFi, vCard, email, SMS and phone — customize colors, size, error correction and logo overlay. Download as PNG or SVG.

Open reviewed tool

Readability Checker

Writing

Analyze text readability with 6 formulas: Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, Coleman-Liau, SMOG, and ARI with SVG gauge and sentence complexity.

Open reviewed tool

Regex Tester

Developer

Test regex patterns with real-time match highlighting, capture groups, replace mode, and a built-in cheatsheet.

Open reviewed tool

Scientific Calculator

Math

Full scientific calculator with dark theme UI, trig functions (sin/cos/tan), logarithms, factorial, powers, memory (M+/M-/MR/MC), degree/radian toggle, parentheses, keyboard input, and calculation history.

Open reviewed tool

URL Encode/Decode

Developer

Encode and decode URLs with full URL parser showing protocol, host, path, query params, and fragment. Query string builder, bulk mode, encodeURI vs encodeURIComponent toggle, and live conversion.

Open reviewed tool

UUID Generator

Developer

Generate UUID v4 with bulk generation (1-100), format options (standard, uppercase, no dashes, Base64), UUID validator with version detection, click-to-copy, download as TXT, and generation history.

Open reviewed tool

Start using FastTool today

Pick a job, open the right utility, and keep the workflow moving. No signup needed.

Browse 50 reviewed tools Try a popular tool