FANJIANbrowser-side workbench
WORKBENCH / 10 CALIBRATED UTILITIES

Finish the calculation.
Keep the raw input.

Focused calculators and file tools that run where the work already is: in your browser.

Open the workbench ↓No sign-up · no tool-input upload
DATA PATH / THIS TAB
01Your inputnumbers, text or files
→
02Browser computeno conversion server
→
03Your resultcopy or download
STAYS ON DEVICE
INDEX

Pick the job, not a category maze.

Every page contains a working tool, the formula or processing rule, and its limits.

Marketing

MKT-01

ROAS Calculator

Measure return on ad spend and the revenue needed to break even.

Open tool ↗MKT-02

CPM, CPC, CTR & CPA Calculator

Calculate the paid-media metrics that belong in one campaign view.

Open tool ↗

Business

FIN-01

Profit Margin Calculator

Convert revenue and cost into profit and margin without spreadsheet setup.

Open tool ↗FIN-02

Markup Calculator

Translate cost and selling price into markup, margin and gross profit.

Open tool ↗

Finance

FIN-03

Compound Interest Calculator

Model a starting balance, monthly deposits and compounding over time.

Open tool ↗FIN-04

Mortgage Payment Calculator

Estimate principal-and-interest payments for a fixed-rate loan.

Open tool ↗

Operations

OPS-01

Business Days Calculator

Count weekdays between dates or add working days to a start date.

Open tool ↗

Developer

DEV-01

CSV ↔ JSON Converter

Convert tabular CSV and JSON arrays locally without uploading data.

Open tool ↗

Media

IMG-01

Private Image Compressor

Resize and compress JPEG, PNG or WebP images in the browser.

Open tool ↗

Documents

PDF-01

Private PDF Merger

Combine multiple PDF files locally and download one document.

Open tool ↗
OPERATING NOTES

Small tools should be exact.

We document assumptions, keep core actions available without registration, and do not disguise advertisements as results or download buttons. Finance tools are mathematical scenarios, not professional advice.

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