CalcLab ProGet a number for free.
Get a number for free.
Get a plan with Pro.
Calculators stay 100% free. Pro turns each result into an exportable plan, document, or workflow you can act on or share.
Free
Forever$0/no card needed
- Core 20+ calculators
- Privacy-first browser-side calculation
- Every formula sourced + explained
- Light/dark themes
- Mobile-first, accessible UI
Pro
Most popular$7/month
or $49/year · save 41%
- Pro-only tools: LLM cost optimizer, manuscript formatter, batch converters
- Cloud-synced workloads — pick up across devices
- Shareable result links (calclab.com/r/…) for clients, lenders, partners
- Exportable PDF reports for every calculator
- Multi-scenario comparison (3+ side-by-side)
- Bulk CSV operations (margin, salary, GPA)
- Personalized planners (academic, weight loss, payoff)
- Goal reverse-calculator (compound interest, payoff)
- Saved workloads + history
- Priority email support
- Early access to new tools
7-day free trial. Cancel anytime.
Cloud-synced
Workloads, scenarios, and history sync across every device. Open any tool, pick up where you left off.
Shareable links
Send a calclab.com/r/… link to your client, lender, or partner — they see the result with your name on it.
Pro-only tools
LLM cost optimizer, manuscript formatter, batch converters, multi-scenario compare. Built for serious users.
What's in Pro, by category
Finance
- Mortgage 3-scenario PDF + amortization schedule
- Compound interest goal reverse-calc + report
- Student loan: standard vs IDR vs refi vs avalanche PDF
- Bulk CSV margin/markup for SKU catalogs
- Job offer comparator (true hourly ranking)
Health & Fitness
- TDEE → 7-day meal plan PDF
- Keto macros → grocery list + recipes
- Calorie deficit week-by-week roadmap
- Pregnancy weight tracker + OB-ready chart
- Peptide injection log & cycle tracker
Construction
- Concrete project cost estimator (materials + labor)
- Full fence project quote (posts + panels + gate)
- Multi-zone landscape estimator
- Solar ROI report (buy vs lease vs PPA)
Education
- Academic planner (semester-by-semester roadmap to graduation)
- Application-ready GPA report
Developer
- LLM cost optimizer (paste prompts, get cheapest model)
- Saved workloads + cost alerts
File Converters & Writers
- Batch HEIC/WebP/AVIF conversion
- PDF ↔ EPUB ↔ MOBI conversion
- Manuscript formatter (KDP / Smashwords)
- Word count tracker, readability score
Frequently asked
- What's free vs Pro?The 20+ core calculators are free with no signup — bring your number, leave with an answer. Pro unlocks the full toolbelt: LLM cost optimizer, manuscript formatter, batch converters, cloud-synced workloads, shareable result links, PDF reports, multi-scenario compare, planners, and bulk CSV ops.
- What's the difference between monthly and yearly?Yearly is $49 — that's $4.08/mo, a 41% discount versus the $7/mo price. Same features either way. Cancel anytime.
- Can I cancel anytime?Yes. Cancel from your account page; you keep Pro features until the end of the billing period. The 7-day free trial lets you test every Pro feature risk-free before paying.
- Are my files & inputs private on Pro?Yes. Pro adds features but doesn't change our privacy model. File converters still run 100% in your browser; calculator inputs still never leave your device unless you explicitly export a PDF.
- Do you have a team plan?Coming soon. If you need 3+ seats today, email calc@3stf.com and we'll set you up manually.
Try Pro free for 7 days.
No credit card. Cancel anytime.