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Encode or decode letters and digits

For a technical exchange, a coding lesson or a conversion check, this gives learners and developers a readable result. Encode or decode letters and digits.

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Word Counter
Change Case
Remove duplicates
Sort rows
Invert text
Clean Whitespace
Slug Generator
Search and Replace
JSON Formatter
JSON Minifier
Base64 Encoder
URL Encoder
HTML Entities
Unix Timestamp
Base Converter
Color Converter
UUID generator
Password Random
Random number
Lorem Ipsum Generator
Extract emails
Extract URLs
Number the lines
Text to list
CSV and JSON
CSV viewer
CSV Separator Converter
Sort a CSV file
Filter a CSV File
Select CSV columns
Remove CSV duplicates
CSV column statistics
CSV to HTML Table
XML Formatter
XML minifier
XML Validator
XML to JSON
JSON to XML
YAML to JSON
JSON to YAML
Markdown preview
Markdown to HTML
HTML to Markdown
Text fingerprint
File fingerprint
HMAC Generator
PBKDF2 derivation
SRI Generator
Fingerprint checker
AES-GCM Encryption
AES-GCM decryption
RSA key generator
Secure random bytes
TOML to JSON
JSON to TOML
INI to JSON
JSON to INI
ENV to JSON
JSON to ENV
JSONL to JSON
JSON to JSONL
SQL Formatter
JSON to TypeScript
HTML Formatter
HTML Minifier
CSS Formatter
JavaScript Formatter
JavaScript Minifier
TypeScript Formatter
GraphQL Formatter
GraphQL Minifier
SQL Minifier
JSON Schema Generator
URL parameters
JWT reader
CSS Minifier
Random color
Dice roll
Remove empty rows
Add prefix and suffix
Repeat text
Character Frequency
Sort JSON keys
Regex tester
Text to hexadecimal
JSON Paths
Coin toss
PIN code generator
Meta Tag Generator
Open Graph Generator
UTM Constructor
robots.txt Generator
JSON-LD Generator
HTML to Text
Escape an expression
Email obfuscator
Percentage calculator
Rule of three
VAT calculator
Temperature Converter
Size Converter
Ratio calculator
Date difference
Duration Converter
URL analyzer
Domain Validator
Email Validator
IPv4 Validator
UUID validator
Validator IBAN
Luhn Validator
Password analyzer
ROT13 Encoder
Caesar Cipher
Morse code
Text and binary
Unicode Code Points
JSON String
NATO phonetic alphabet
Character codes
Age calculator
Add days
Business days
ISO week
Day of the Year
Leap year
Day of the week
Time Zone Converter
Base32 encoder
Punycode
Quoted-printable
Number formatting
Numbers in words
Bitwise calculator
Unit price comparison
Tip calculator
Body mass index
Torque converter
Fuel consumption converter
Data rate converter
Percentage change
Modular arithmetic
SIREN validator
BIC validator
ISBN validator
Card brand detector
Truncate text
Text columns
Matrix calculator
Text compare
Natural sort
Cron builder
Duration sum
Date range generator
Countdown
Type scale
Color blindness simulator
SVG optimiser
Amortisation schedule
Tax bracket calculator
Currency format
Payback period
Net present value
A/B significance
Sample size
UTM parser
Funnel calculator
Robots.txt tester
Structured data validator
Title length check
JWT builder
Secret scanner
MTU calculator
MX records
Breakpoint tester
Test data generator
EAN-13 barcode
Bulk slugs
Invoice numbering
Legal notice
Terms of sale outline
Quote calculator
EU VAT validator
Email signature
SPF builder
DMARC builder
List cleaner
Merge CSV
Split CSV
Pivot table
CSV to Markdown
Placeholder image
Keyword extraction
Tone detector
Readability score
Text anonymiser
Guided alt text
Meeting agenda
Project checklist
Creative brief
Persona sheet
Editorial calendar
Podcast chapters
Guest brief
Clean a transcript
Storyboard
Video chapters
WebVTT subtitles
Text summary
Change the tone
Simplify a text
Style check
Frequently asked questions
Catchy headlines
Article outline
Meeting minutes
Client follow-up
Review reply
Handle an objection
Professional email
Episode show notes
Video title and description
Thumbnail plan
SIRET validator
Page weight
Performance budget
Responsive images
Lazy-loading audit
Critical CSS
Preload hints
Compare two .env files
Build an HTTP request
Internal link map
On-page audit
SVG favicon
Geo QR payload
Crypto payment QR
Batch QR payloads
Certificate decoder
Dominant palette
Levels histogram
Subject-aware crop
Mask areas
Foldable booklet
Split a PDF by size
Image collage
Sprite sheet
Convert audio to WAV
Trim audio
Merge audio files
Adjust audio volume
Audio fade in and out
Change audio speed
Find silences in audio
Read audio tags
Compare two DNS resolvers
Check DNSSEC signature
Check if a password was breached
Convert video to GIF
Trim a video
Rotate a video
Add a watermark to a video
Traceroute
CORS tester
Cookie inspector
Open Graph preview
Roman numerals
Prime number test
Prime factors
GCD and LCM
Statistical Summary
Fraction Simplifier
Decimal to fraction
Scientific notation
Color contrast
HEX to HSL
Pixels and REM
Gradient generator
Shadow Generator
Border radius
CSS Fluid Size
Color palette
IPv4 and integer
CIDR calculator
Subnet Mask
Port references
HTTP status codes
MIME Types
User-Agent analyzer
URL Solver
Length Converter
Mass Converter
Speed Converter
Area Converter
Volume Converter
Pressure Converter
Energy converter
Angle converter
Quadratic Equation
2x2 Linear System
Combinations
Permutations
Standard Deviation
Geometric Mean
Arithmetic sequence
Fibonacci sequence
Loan payment
Compound Interest
Simple Interest
Discount Calculator
Gross margin
Break-even point
Annualized Growth
Inflation Projection
Return on investment
Advertising return
Cost per acquisition
Cost per click
Cost per thousand
Click-through rate
Conversion rate
Customer Lifetime Value
Keyword Density
SERP preview
Heading structure
HTML Link Extractor
Canonical tag
hreflang generator
Redirection Plan
XML Sitemap Input
Password Entropy
Passphrase Generator
API Key Generator
TOTP secret
chmod converter
Identifier Hash
Security headers
CSP Constructor
Resize an image
Compress an image
Convert an image
Crop an image
Rotate and flip
Grayscale Image
Add watermark
Image information
Merge PDFs
Extract from PDF pages
Delete pages PDF
Reorganize a PDF
Rotate PDF pages
Numbering PDF pages
PDF information
Images to PDF
Invert colors
Sepia Filter
Black and white
Blur an Image
Emphasize an image
Brightness and Contrast
Rasterize an image
Add a border
Round the corners
Circular crop
Invert PDF pages
Duplicate PDF Pages
PDF Watermark
Crop PDF pages
Edit PDF Metadata
Erase PDF metadata
Text and URL QR
Wi-Fi QR
Contact Form QR
Email QR code
QR SMS Generator
Phone QR
Event QR code
Code 128 barcode
Full domain diagnostics
DNS Lookup A
AAAA DNS lookup
MX DNS Lookup
DNS TXT Lookup
NS DNS lookup
SOA DNS lookup
DNS CNAME lookup
CAA DNS Lookup
Reverse DNS lookup
Domain Whois
IP address Whois
HTTP header analysis
Site speed test
TLS certificate analysis
TCP Port Test
Check SPF
DMARC Check
MTA-STS Check
TLS-RPT Check
IP Blacklist Check
What is my IP
SRV DNS lookup
NAPTR DNS Lookup
DKIM Check
BIMI Check
Complete email health
Verify robots.txt
Verify the sitemap
Security header audit
Verify a redirect
Common public ports
Remove image metadata
Edit Opacity
Add background
Center square crop
Social media formats
Thumbnail Generator
Color overlay
Add a vignette
Posterize an image
Hue and saturation
Gamma correction
Auto contrast
Duotone effect
Remove solid background
Icon Generator
Reduce noise
Color temperature
Add blank page
Add text to PDF
Flatten PDF forms
Change Page Format
Assisted CV builder
Assisted cover letter
AI descriptions for social media
AI-assisted hashtags
Compress a PDF
Repair a PDF
PDF OCR
PDF to images
Word Excel PowerPoint to PDF
Extract text from an image
Smart background removal
Compress a video
Optimize PDF for Web
Universal Image Converter
Optimize HD Image
PDF to Text
PDF to SVG
Extract PDF images
Grayscale PDF
Convert to PDF/A
Flatten PDF annotations
Correct image orientation
Erase image metadata
Image to High-Quality PDF
Convert Video
Extract a video thumbnail
Extract audio from a video
Invoice Generator
Quote Generator
Receipt Generator
Purchase order
Measurable Campaign QR
Location QR
Payment QR
QR for App
QR for Social Network
Black and white threshold
Edge detection
Relief effect
Solarization effect
Replace a color
Add grain
Correct exposure
Tinting an Image
Channel mixer
Equalizes histogram
Shadows and Highlights
Reduce colors