Feature Flags

Ship code behind flags. Release when ready.

Boolean, string, number, and JSON flags with instant toggling. Deploy behind flags and control who sees what — without redeploying.

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Feature Flags
production
new-checkout
boolean · 100%
ai-assistant
boolean · 25%
dark-mode-v2
boolean · off
checkout-layout
string · "redesign"
Coming Soon

Schedule flag changes ahead of time.

Plan product launches, maintenance windows, and timed experiments. Set it and forget it — your flags activate exactly when you need them.

Scheduled Change
SCH-2026-0218
PENDING
Target Flag
new-checkout-flow
boolean · production
Action
Enable flag
set to true
Scheduled Activation
Date
Feb 20, 2026
Time
09:00 UTC
Timezone
UTC+0
Countdown ~2 days remaining
Created Feb 18, 2026 Activates Feb 20, 2026
Set date & time
Automate maintenance
Coordinate launches
Timezone aware
terminal
200 OK
Request
curl -H "Authorization: Bearer sk_your_api_key" \
https://flagdash.io/api/v1/flags/new-checkout \
-G -d "user_id=user_42" \
-d "country=US" \
-d "plan=premium"
Response
{
"key": "new-checkout",
"value": true,
"flag_type": "boolean",
"enabled": true,
"matched_rule": "country=US AND plan=premium"
}
Context-Aware API

Evaluate flags with
user context.

Pass user attributes and get precisely targeted flag values. One API call gives you the evaluated result based on targeting rules, rollout percentage, and A/B test assignments.

  • RESTful JSON API with bearer auth
  • SDKs for JS, React, Node, Go & Python
  • Sub-3ms evaluation with consistent hashing
  • Pass any attribute: user_id, country, plan, email

Precise control with targeting & experiments

Deliver the right experience to the right users with rule-based targeting and weighted A/B tests.

Targeting Rules
3 rules active
RULE 1
country equals "US" AND plan in "premium", "enterprise"
Then serve true
RULE 2
email ends_with "@flagdash.io"
Then serve true (internal beta)
eq neq contains in not_in regex gt / lt starts_with ends_with
A/B Testing
experiment
checkout-redesign
string · 2 variations
A Control
50%
value: "classic"
B Treatment
50%
value: "redesign"

Consistent Hashing

Same user_id always maps to the same bucket. Ramping from 10% to 25% adds new users without reassigning existing ones.

Everything you need for safe releases

Decouple deployment from release. Ship code any time and control who sees what.

Instant Toggle

Enable or disable any flag with a single click. Changes propagate instantly — no deploy needed.

Percentage Rollouts

Gradually roll out to 1%, 10%, 50% of users. Consistent hashing ensures stable cohort membership.

Boolean, String, Number & JSON

Not just on/off. Use string, number, or JSON flags for multivariate experiments and complex configurations.

Targeting Rules

Target by country, plan, email, or any custom attribute. Combine conditions with AND/OR logic for precise segments.

A/B Testing

Define weighted variations for experiments. Consistent hashing ensures stable assignment across all evaluations.

Scheduled Changes

Schedule flag changes ahead of time. Plan launches, maintenance windows, and timed experiments automatically.

Ready to decouple deploy from release?

Start using feature flags in under 5 minutes. Free forever for small projects.

Get started for free Read the docs