SmartToolsHub
Smart Calculators. Instant Results.

Free online tools

Free Online Calculators, Converters, PDF Tools, and Generators

Use free online calculators, PDF tools, converters, generators, and productivity tools without sign-up. Browse by category or open one of the most-used tools below.

80 free tools 10 categories Browser-based No sign-up
Browse all categories Request a tool

Popular free online tools

Start with high-demand calculators, PDF tools, converters, and utilities that already perform well in the SmartToolsHub catalog.

real-estate

Mortgage Calculator

Estimate monthly mortgage costs using home price, down payment, APR, taxes, insurance, HOA, PMI, and extra payment assumptions, with a first-year amortization preview.

mortgage calculatormonthly mortgage paymenthome loan calculator
Open tool
real-estate

Home Affordability Calculator

Estimate how much house you can afford using income, monthly debts, down payment, APR, taxes, insurance, HOA, PMI, closing costs, and front-end and back-end DTI targets.

home affordability calculatorhow much house can i afforddti calculator
Open tool
finance

Tax Calculator

Estimate federal income tax, state income tax, and employee payroll taxes for tax year 2025 with filing-status support, itemized deductions, and either a federal-taxable or custom state tax base.

tax calculatorfederal taxstate income tax
Open tool
technology

PDF Compressor

Compress PDF files in the browser with scale and quality controls, before-and-after size comparison, and instant download.

pdf compressorcompress pdf onlinereduce pdf size
Open tool
technology

Internet Speed Test

Test internet download speed, upload speed, ping, and jitter with same-origin server checks, selectable sample profiles, and shareable settings.

internet speed testwifi speed testdownload speed test
Open tool
real-estate

Rent vs Buy Calculator

Compare renting and buying with mortgage costs, taxes, insurance, HOA, maintenance, PMI, appreciation, selling costs, rent growth, and investment return assumptions.

rent vs buybuy or renthome buying calculator
Open tool
finance

Compound Interest Calculator

Project future investment growth with starting principal, recurring monthly contributions, contribution growth, compounding frequency, inflation, and optional target tracking.

compound interestinvestment growthfuture value
Open tool
technology

CIDR Calculator

Calculate IPv4 CIDR subnet details from an IP address and prefix length, including network address, broadcast address, subnet mask, host range, usable hosts, and address classification.

cidr calculatorsubnet calculatoripv4 network
Open tool
technology

JSON Formatter & Validator

Validate, format, and minify JSON with optional key sorting, output metrics, and one-click copy or download.

json formatterjson validatorjson beautifier
Open tool
technology

Base64 Encoder & Decoder

Encode plain text to Base64 or decode Base64 back to text with optional URL-safe output and padding controls.

base64 encoderbase64 decoderurl safe base64
Open tool
productivity

Text Case Converter

Convert text across sentence, title, uppercase, lowercase, snake_case, kebab-case, camelCase, and PascalCase styles.

text case convertertitle case convertersnake case converter
Open tool
education

Citation Generator

Generate in-text or reference-list citations for websites, books, and journal articles with selectable APA 6, APA 7, MLA, and Chicago styles.

citation generatorapa citationmla citation
Open tool

Resume faster

The live site can remember recent tools and favorites locally in your browser so repeat visits start faster.

Recent tools

Open a tool in the interactive app and it appears here for quick return visits.

Favorite tools

Save high-repeat tools from any tool page to keep them pinned on the home page.

Browse free tool categories

Explore the full catalog by topic and use the category pages to discover related tools with stronger internal linking.